Billionaire Mark Cuban was just 12 years old when he started his first side business, so he knows what it takes to start a business at a young age.
And, he says there’s one simple thing to keep in mind if you want to do it, too.
“The key to starting a business when you’re young is to do things you can do yourself — things you can do on your own time,” Cuban recently told a group of high school students at the Lewisville High School in Texas.
That means starting with what you know, he noted.
“If it’s a product, make something that’s easy to get and easy to sell,” Cuban said, adding, “It really comes down to one simple thing. The best businesses are the things that can check them out and do it yourself. That’s what being an entrepreneur is all about.”
Cuban started learning to run his own business early as a teenager selling trash bags door-to-door in a Pittsburgh suburb. Later, he sold a variety of collectibles, from baseball cards to coins and stamps, saying the proceeds helped pay for his college tuition.
In each of these cases, Cuban used household items and collectibles that were accessible to a child and sold them for a profit—following his own advice for teenagers today.
Similarly, as a college student, he worked as a bartender and gave dance lessons to earn extra money. Cuban later showed off his dancing skills publicly by appearing on Dancing With the Stars in 2007, finishing 8th in the competition.
“I’ve been a bum … I’ve always sold. I always had something going on. That was just my nature,” Cuban said during a 2016 episode of ABC’s “Shark Tank.”
Now, Cuban says he regularly tells kids and teenagers looking to start their own businesses to do what he did. Build around “something they can do or a service they can provide to friends, family and neighbors,” he told CNBC Make It in September.
This is easier said than done, of course: Successfully launching and growing your business is extremely challenging. Approximately 20% of new businesses fail within a year of starting, according to data from the US Bureau of Labor Statistics.
“Being an entrepreneur and starting a business doesn’t mean it’s going to be easy and suddenly you make a lot of money,” Cuban told students at Lewisville High School. “Being an entrepreneur is the hardest way.”
If it were easy, he added, “you’d all already do it and come on Shark Tank and take my place.”
Finding something that you can control and do yourself is quite difficult. Being great at it — which, by the way, is Cuban’s No. 1 rule for making money — is much harder.
It includes extensive research of your business plan and potential competition, seeking funding and creating backup plans to allow flexibility if you need to adapt on the fly, the billionaire previously said.
As long as you don’t mind putting in the work, especially after you choose your business opportunity, a world of opportunities can open up for you, Cuban told the high school students.
“If you are willing to take the initiative and start a business, anything is possible,” he said.
Disclosure: CNBC owns the exclusive off-network cable rights to “Shark Tank.”
Register now: Get smarter about your money and your career with our weekly newsletter
Why Mark Cuban Called This ‘Shark Tank’ CEO Who Brought in Millions ‘a Great Case for What Not to Do’
Mark Cuban: Here’s why you should teach your kids to be entrepreneurs