Advice for young entrepreneurs

Billionaire Mark Cuban started his first side business when he was just 12 years old, so he knows what it takes to start a business young.

And there’s one simple thing to consider if you want to do that, he says.

“The key to starting a business while you’re young is what you can do yourself—what you can do with your time,” Cuban recently told a group of high school students at Louisville, Texas.

That means starting with what you know, he pointed out.

“If it’s a product, make it easy to get and easy to sell,” Cuban said. What is an entrepreneur? “

Cuban famously began learning early to run his own business as a pre-teen selling garbage bags door to door in a Pittsburgh suburb. He then sold a variety of collectibles, from baseball cards to coins to stamps, and says the proceeds helped pay his college tuition.

In each of these cases, Cuban followed his own advice to today’s teenagers, using household items and collectibles accessible to children and selling them to make a profit.

Similarly, as a college student, he worked as a bartender and taught dance lessons to earn extra money. By doing so, she publicly showcased her dancing skills.

“I was a hustler… I was always selling. I was always doing something. That was my nature,” Cuba said on a 2016 episode of ABC’s “Shark Tank.” rice field.

Now Cuban says he regularly tells kids and teenagers who are starting their own businesses to do what he did. Building around “something they can make or a service they can provide to their friends, family and neighbors,” he told CNBC Make It in September.

Of course, easier said than done. Starting and growing your own business is very difficult. According to data from the U.S. Bureau of Labor Statistics, about 20% of new businesses fail within his first year of launch.

“Being an entrepreneur and starting a business is not easy and suddenly you can make a lot of money,” Cuban told students at Louisville High School. “Being an entrepreneur is the harder way.”

If it were easy, he added.

It’s very difficult to find things you can control and do yourself. Learning to do it well, incidentally, the number one rule for Cubans to make money, is much more difficult.

That includes extensively researching your business plan and potential competitors, seeking funding, and creating a back-up plan that allows you the flexibility to adjust on the fly.

As long as you don’t mind doing the job, a world of opportunities can open up for you, especially after choosing a business opportunity, Cuban told high school students.

“If you’re willing to take the initiative and start a business, anything is possible,” he said.

Disclosure: CNBC owns the exclusive rights to the “Shark Tank” off-network cable.

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