Even billionaires think about starting side hustles.

If Mark Cuban were 16 years old again and “needed to make some extra money,” he’d start one specific side hustle in just three steps, he tells CNBC Make It.

First, he’d learn how to write prompts for artificial intelligence language models like OpenAI’s ChatGPT or Google’s Gemini. Next, he’d teach his friends how to use those prompts on their school papers. “Then, I would go to businesses, particularly small- to medium-sized businesses that don’t understand AI yet,” says Cuban. “Doesn’t matter if I’m 16, I’d be teaching them as well.”

More than half of Gen Zers in the U.S. currently have side hustles, a LendingTree report found in February. AI prompt engineering — or, the ability to phrase inquiries to chatbots to get desired responses — can be a particularly lucrative opportunity. The average pay for AI tutors starts at about $30,000 per year, and full-time AI prompt engineers can make up to $129,500, according to job board platform ZipRecruiter.

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You don’t need a college degree to become an AI prompt engineer, but you do need practice — and, often, certifications — to learn how those large language models operate. Some online certification courses, like Vanderbilt University or IBM’s offerings on Coursera, say you can master the basics in one month.

Cuban’s hypothetical side hustle is more high-tech than his actual first job, selling garbage bags door-to-door to his neighbors outside of Pittsburgh at age 12 to save up for a new pair of basketball shoes. He continued to earn extra cash as a teenager by selling collectibles like baseball cards, stamps, and coins, eventually helping him pay to attend Indiana University. There, he bartended, hosted parties with cover charges and even picked up work as a dance instructor.

After a brief post-college stint in banking, Cuban turned to entrepreneurship full-time. He sold his first company, a software startup called MicroSolutions, to CompuServe for $6 million in 1990. His second company, audio streaming service Broadcast.com, made him a billionaire when he sold it to Yahoo for $5.7 billion in 1999.

Today, Cuban has a net worth of $5.7 billion, according to a Forbes estimate. He spends much of his time advocating for his online pharmacy Cost Plus Drugs, which aims to make a variety of common prescription drugs more affordable by selling them at cost, plus a 15% markup.

 “I was a hustler … I have always been selling,” he said during an episode of ABC’s “Shark Tank” that aired in 2016. “I always had something going on. That was just my nature.”

Correction: This story has been updated to reflect that Mark Cuban sold garbage bags door-to-door at age 12.

Disclosure: CNBC owns the exclusive off-network cable rights to “Shark Tank,” which features Mark Cuban as a panelist.

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What if I told you that unleashing success starts with realizing how successful you already are?

It’s true. As a leadership and success expert I get asked a lot about “keys to success.” My first response is always: “Before you start changing, adding, or subtracting, spend some time appreciating.”

Success is more than just how much money you make, what job title you’ve achieved, or what accomplishments you’ve stacked up. There’s nothing wrong with any of that, but true success is broader. It’s about the kind of life you’re living and who you’ve chosen to become.  

When you think about success in a more holistic way, it requires resilience, confidence, and other aspects of mental strength I talk about in depth in my recent book, “The Mentally Strong Leader.” 

A true measure of success requires introspection on a set of questions beyond the typical “how much” and “how high” metrics. If you can answer “yes” to the following six questions, you’re more successful — right now — than you may have realized.

The little things you do every day exemplify who you are. The little impressions you make leave a big, permanent impression. The question is: Do you choose to behave in line with your values? For example, if a core value is kindness, are you consistently kind, even when it’s hard? 

Intentionally living your values shows you’re centered and disciplined, and both are forms of success. Doing this is no small feat — it’s not easy to clearly articulate your values, let alone intentionally live them. 

If you’d like to start by articulating your values, there’s an exercise in “The Mentally Strong Leader” to help you do just that.

We all need to work in our lives, navigating our daily routines to get stuff done. But sometimes we get jammed up in habits, systems, or processes that no longer serve us — or anyone — well. 

Greater success comes from working on your life, too.

Are you stepping back from time to time to envision the life you really want to live and the person you really want to be? Are you reflecting to discern if you’re heading where you really want to go?

This is how you spot unhelpful patterns and habits you’ve fallen into — and give yourself a chance to change them.  

As the Rolling Stones once lamented, “You can’t always get what you want.” But happiness and success flow from focusing on what you do have. 

I know from my own experience — and I imagine you do, too — that it’s easy to get caught up feeling like what you have is never enough, to always be looking to the next thing, to constantly seek the next rung of the ladder to climb. 

The ability to consistently show gratitude for all you have and have already accomplished, versus always needing more, is a key trait of the most successful people.

As you strive for success, you’ll make mistakes. The key is: How do you react?

Do you let mistakes beat you down? Or do you see yourself as successful only if you’re making mistakes, making incremental improvements, and adapting along the way? 

True success requires you to fall in love with the process of improving and achieving, not just the achievement itself.

That can be difficult at times, especially when the work might feel repetitive, uninteresting, or far removed from what you’re ultimately aiming to do or get. But it’s attention to the little stuff that pays off in big moments.

For example, I’m often asked about becoming a professional speaker. People tell me, “I’d love to get paid to talk onstage for an hour.” But to do so requires intensive research to uncover insights worth getting paid to talk about and hours of repetitive rehearsal. It’s a process. 

As Ina Garten points out with her new memoir, you have to “be ready when the luck happens.” 

A friend of mine told me recently she felt like a failure for not getting a promotion she wanted. But when I pushed her to define what success really meant to her, it wasn’t that promotion at all.

She’d fallen into the trap of thinking, “This is what I’m supposed to want.” She realized success to her was having a team that she could coach and nurture — something she could achieve in the role she was already in.

It breaks my heart when I hear someone say they don’t feel successful based on someone else’s definition instead of their own. When you define what success means to you, you might discover how successful you already are.

Scott Mautz is a popular speaker, trainer, and LinkedIn Learning instructor. He’s a former senior executive of Procter & Gamble, where he ran several of the company’s largest multi-billion-dollar businesses. He is the author of ”The Mentally Strong Leader: Build the Habits to Productively Regulate Your Emotions, Thoughts, and Behaviors.” Follow him on LinkedIn.

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When I was a child, my parents would buy lottery tickets and talk about what they’d do if they ever won. It was a fun discussion around the dinner table, but it was a dream that always seemed out of reach. I often thought to myself, “Why not find a way to get rich with better odds?” 

Now, as the parent of two young kids and the owner of my own business, I feel like I have hit the jackpot — but not by leaving anything to chance. 

Four years ago, I left an unfulfilling 9-to-5 job in higher education administration and started selling digital products on Etsy. Today, I make $10,000 or more per month in passive income from four income streams. 

These are the three books that shifted my mindset about money, helped me build wealth and gave me the ability to live life on my terms.

In “Change Your Questions, Change Your Life,” Marilee Adams, PhD, a leadership expert, professor, and entrepreneur, explains there are two types of questions we can ask ourselves. “Judger” questions are blame-focused, while “learner” questions are solution-focused.

After I read this book, I realized how much my internal dialogue influenced my mindset and the results I achieved. When I faced challenges, instead of being hard on myself and saying “What’s wrong with me?” I started asking, “What can I learn?”

Adams has a great resource called a Choice Map. It’s essentially a flow chart to help avoid judgmental language and overcome roadblocks.  

When I started taking the course that ultimately helped me start my passive income business, for example, I doubted whether I could succeed. However, instead of giving up, I used the choice map and shifted my mindset by asking, “What’s best to do now?” 

This question helped me stay focused, break tasks down into manageable steps, and persist, until I ultimately built the foundation for my passive income business and started to see real financial results.

No. 1 lesson: The language we use to talk about ourselves can shape our reality.

“The Simple Path to Wealth” grew from a series of letters about money and investing that JL Collins, a blogger and expert in personal finance and investing, wrote to his teenage daughter.

At the beginning of his book, he shares “a few key guidelines” about money. Some of my favorite pieces of Collins’ advice are: 

• “Spend less than you earn — invest the surplus — avoid debt.”
• “Avoid fiscally irresponsible people. Never marry one or otherwise give him or her access to your money.”
• “Try saving and investing 50% of your income. With no debt, this is perfectly doable.”
• “When you can live on 4% of your investments per year, you are financially independent.”

To follow his advice, I sat down and created a budget that allowed me to spend less than I earned and invest the difference. Then, in 2015, my husband and I decided to save and invest 50% of our income in low-cost index funds. 

We didn’t chase complicated strategies or try to time the market. We simply focused on consistent, automated contributions to index funds. 

After nine years, we are now at a point where we can work more fulfilling jobs, even if they pay less, because we have a nest egg working in the market for us. Collins calls this “F.U. Money” — enough money not to have to answer to the whims of a boss if you don’t want to, because you are no longer living paycheck to paycheck. 

No. 1 lesson: Avoid debt. Save and invest your money in a low-cost index fund. Use invested money to buy your freedom.

Bill Burnett and Dave Evans, professors and innovators in design thinking, are known for teaching a popular elective at Stanford University called “Design Your Life,” which was the foundation of the book.

In “Designing Your Life,” Burnett and Evans encourage iteration and embracing experimentation, rather than waiting for the “perfect” path to appear.

I first read this book while studying positive psychology in grad school. It was 2020, I had just had my second child, and I was dreading the idea of working a full-time office job. 

By putting the exercises from this book in place, I used design thinking to explore careers that would help me lead with my strengths. I realized that while hours of meetings drained me, project-focused work energized me and helped me get into a creative flow.  

I often return to this book because, as Burnett and Evans say, “a well-designed life is a life that is generative.” As much as we try to plan for the future, our goals and dreams constantly evolve, and life is full of surprises.

I thought earning passive income would be the key to my happiness. However, once I had it, I realized I missed the human interaction I got at work. Continuing to iterate helped me to find teaching and writing — roles that allow me to work on projects and interact with people without having to do a traditional 9-to-5.

No. 1 lesson: Happiness comes from designing a life that works for you.

Rachel Jimenez is an entrepreneur, professor and mom of two, with a passion for helping others achieve their personal, professional and passive income goals. She runs an Etsy store as well as a blog, Money Hacking Mama, where she shares financial wisdom and practical advice for women navigating their careers, businesses and life.

Want to earn more money at work? Take CNBC’s new online course How to Negotiate a Higher Salary. Expert instructors will teach you the skills you need to get a bigger paycheck, including how to prepare and build your confidence, what to do and say, and how to craft a counteroffer. Sign up today and use coupon code EARLYBIRD for an introductory discount of 50% off through Nov. 26, 2024.

“John Wick” might never have gone on to become a billion-dollar-grossing film franchise if not for the financial intervention of Eva Longoria, the original film’s directors revealed this week.

In an interview with Business Insider for the film’s 10th anniversary, Chad Stahelski and David Leitch — who directed the film together, despite only Leitch receiving a credit — said that the Keanu Reeves action flick was mere days away from having to shut down production due to a lack of funding.

“We were less than a week out and we lost almost $6 million on a gap financing,” Stahelski told the publication. “We had all put in everything, including Keanu. And we were still short. So we were shut down.”

In a last ditch effort to save the production, CAA offered a number of its actors the chance to finance the remaining $6 million with the promise that they would be the first to be paid back once the film hit theaters.

Longoria reportedly took CAA up on the opportunity, though Leitch and Stahelski didn’t know it at the time.

“She came to the rescue and she provided the gap financing,” Stahelski said. “Literally less than 24 hours before we had to lock the doors on the movie and walk away, [our producer] said ‘We’ve got the investor, we’ve locked the gap.’”

Following the film’s box office success — it grossed $86 million on its estimated budget of $20 million to $30 million — the directors took Longoria out for lunch in Los Angeles as a thank you.

Leitch said he ran into the actress last year at awards season events and that the two reminisced about her financial intervention.

“She was like, ‘Wow, that was the best money I’ve ever spent,’” he said. “It paid back significantly for her.”

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If you’re saving in a tax-advantaged retirement account, you generally have one of two flavors to choose from.

The choice lies in when and how you’re taxed. “Traditional” versions of 401(k)s and individual retirement accounts are funded with pre-tax dollars, meaning you get a tax break in the year you make contributions. Roth accounts work in reverse: You pay taxes up front, but can withdraw your money tax-free, provided you meet a few rules, in retirement.

The argument over which type of account to use typically revolves around how much money you make. Early-career, low-income workers are better off in a Roth, the thinking goes, because they’d save money by paying taxes when they’re in a low bracket instead of waiting until they’re bringing in more in retirement. High earners, meanwhile, are generally steered toward traditional accounts and their upfront tax break.

However, some money pros don’t think you should bother with that particular calculus.

“I don’t care what tax bracket you’re in,” says Suze Orman, a financial expert and host of the “Women & Money (and Everyone Smart Enough to Listen)” podcast. “You have to be crazy to do anything other than a Roth retirement account.”

Orman’s thinking echoes that of Ed Slott, a certified public accountant, founder of IRAHelp.com and one of the internet’s leading Roth evangelists.

When it comes to the question of paying your taxes now or later, nearly everyone would be wise to pay now for two reasons, he says.

1. Roths don’t tax your gains

Investors in traditional accounts can deduct the amount they put in from their taxable income for the year they made the contribution. But in exchange for that break, they’re generally not allowed to take their money out until retirement without penalty. And when they do finally withdraw it, they owe income tax on all of it — their contributions and their gains.

If the market goes up over the course of your career as an investor — and, historically, it has — then every cent you earn is adding to your eventual tax burden.

“That tax is constantly building,” Slott previously told CNBC Make It. “The values are up, but that means the eventual share that will be going to Uncle Sam will be higher, too.”

Roths, meanwhile, tax your contributions going in. You can withdraw up to what you’ve contributed at any time from a Roth without penalty. And provided you’re 59½ and have owned the account for at least five years, everything you take out of a Roth IRA or 401(k) is tax-free.

2. Roths take advantage of low tax rates

The traditional thinking around traditional versus Roth accounts revolves around your personal tax rate. High earners should pay tax later; low earners should pay it now.

But what about the overall tax rate? After all, the government could raise taxes across the board, which would generally spell bad news for those who put it off.

While no one can predict how tax rates will change in the coming decades, it’s worth noting that tax rates are just about as low as they’ve ever been, says Christine Benz, director of personal finance and retirement planning at Morningstar, and the author of  “How To Retire.”

“Tax rates are low, secularly, compared with where they’ve been historically,” she says. “So the idea is that you’re better off taking your tax medicine now at relatively low tax rates.”

Benz, though, isn’t quite as convinced as Orman or Slott that Roths make the most sense for everyone, period.

For one, if tax rates stay relatively low, the traditional logic may still apply to some retirement savers, she says.

“It depends on the household. For higher-income earners, their tax rates in their peak earnings years may be their highest level in their lifetime,” she says. “So if they can get a tax break on their contributions, that may be the way to go.”

Of course, it can be tricky to pinpoint exactly where you are in your career and retirement savings trajectory, which makes this a decision where professional input may be helpful.

“This is an area where financial planning software, a financial planner, can really add a lot of value to help do some projections in terms of how much you’re contributing, how much you have already and what your tax rate will look like in retirement,” Benz says.

What’s more, Benz doesn’t see the harm in having a mix of money in Roth and traditional accounts for retirees.

“The concept of tax diversification appeals to me. It’s difficult to know where tax rates will go in the future. So having a combination will give you a blend,” she says. “You’re sort of diversifying the tax treatment of your investment assets. I think that makes sense, just as you would diversify other aspects of your investment portfolio across asset classes and across investment styles and sectors.”

Basically, there’s a chance that if you follow Orman and Slott’s advice, and put everything into Roth accounts, you could end up paying more in taxes than you would have had you been a little more strategic.

But as Slott is fond of saying, you end up with a pretty decent consolation prize in retirement: “You’ve locked in a 0% tax rate on your retirement [withdrawals].”

Want to earn more money at work? Take CNBC’s new online course How to Negotiate a Higher Salary. Expert instructors will teach you the skills you need to get a bigger paycheck, including how to prepare and build your confidence, what to do and say, and how to craft a counteroffer. Pre-register now and use coupon code EARLYBIRD for an introductory discount of 50% off through Nov. 26, 2024.

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