When serial entrepreneur and investor Mark Cuban became a millionaire, he had a simple goal: Don't spend all his newfound riches at once.

Upon selling his software company MicroSolutions for $6 million in 1990, Cuban — who took home roughly $2 million, after taxes — quickly called a broker, he told social media personality Jules Terpak in a video interview released Monday.

"I want you to invest for me like a 60-year-old. I don't want you to invest like I'm young, because I want to live off this for a long time," Cuban, now 66, recalled telling the broker.

Cuban, the son of an automobile upholsterer near Pittsburgh, didn't grow up rich. He also knew wealth could be fleeting — he nearly went broke at age 27, after starting MicroSolutions — and dedicated himself to living more like a frugal student, he said.

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Early in his career, that meant living with five roommates, sleeping on the floor and driving a 1966 Buick LeSabre. After becoming a millionaire, it meant living somewhat below the stereotype of his newfound means.

"By the time I sold [MicroSolutions], I had just bought the worst house in the best neighborhood, but I wasn't big into that," said Cuban. "I wasn't big into cars. I wanted to live like a student and just have fun."

His frugality had exceptions: While celebrating the sale with his friends, Cuban bought a $125,000 lifetime pass at American Airlines, he said on the "Club Shay Shay" podcast in October. He also indulged in another aspect of living like a student, he told Terpak: getting drunk and partying.

"I bought this lifetime pass so I could go to any city, anywhere [and] party like a rock star," said Cuban. "I literally would [say] I want to get drunk with as many people as I could."

Experts encourage young investors to take risks

Cuban's strategy of prioritizing low-risk investment strategies essentially became a non-factor in 1999, when he sold his second tech company, an audio streaming service called Broadcast.com, for $5.7 billion.

Becoming a billionaire helped him feel like, "OK, I'm set," he said, giving him breathing room to take on more risky investments. He's known to take bold chances as an investor on ABC's "Shark Tank," and has said that taking smart risks is essential to becoming wealthy.

His mindset today is much closer to most experts' investing advice for young people. Younger investors can generally afford to take bigger risks with higher potential gains than older investors, because they have more time to ride out market fluctuations and recover from any potential losses before they're ready to retire.

Nasdaq CEO Adena Friedman, for example, specifically encourages young people to get comfortable with taking risks. Even experimenting with pocket money can help you learn the realities of the stock market, she said last month while speaking at the Fortune Global Forum 2024.

"Learn by doing — with small amounts of money, or even on platforms where you don't actually have to use real money," said Friedman. "As you get more engaged and more educated, you can start to take more risks ... and then get more confidence."

As for Cuban's habit of living like a student, his party-heavy days are largely behind him, he tells CNBC Make It. He remains committed to not overspending, relatively speaking: He doesn't own yachts, have butlers or hire house cleaners — though he did buy a $40 million jet upon becoming a billionaire, setting a record for largest single e-commerce transaction in history.

He now spends most of his time with his family or running his pharmaceutical startup Cost Plus Drugs, an online pharmacy that aims to make prescription drugs more affordable, he says.

"I think less about making money and more about direction and f---ing things up to benefit as many Americans as I can," says Cuban.

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