The 33-year-old billionaire founded Dropbox, the file-sharing and storage service, at age 24. In January 2014, after his company was valued at $10 billion, Houston joined Forbes' billionaire ranks, where he still holds a spot today.
But in a recent interview with Adam Bryant of The New York Times, Houston said that he told students in his 2013 commencement speech at MIT, his alma mater, that if he had a cheat sheet he could give himself at 22, it would have three things on it: "a tennis ball, a circle, and the number 30,000."
The tennis ball, he said, is about finding the thing you're infatuated with.
"The most successful people and successful entrepreneurs I know are all obsessed with solving a problem that really matters to them," Houston explained. "I use the tennis ball for that idea because of my dog, who gets this crazy, obsessed look on her face when you throw the ball for her."
The circle, meanwhile, is about the idea that "you're the average of your five closest friends, so make sure to put yourself in an environment that pulls the best out of you."
And lastly, the number 30,000 is about making the most of your life.
He said: "When I was 24, I came across this website that says most people live for about 30,000 days. So you have to make every day count."
Now, check out this list of other notable entrepreneurs:
Notable recent entrepreneurs
A 33-year-old billionaire CEO shares what his post-college 'cheat sheet' for life would include
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Rent the Runway co-founders Jennifer Fleiss and Jennifer Hyman attend the 4th Annual Fashion 2.0 Awards at SVA Theater on March 13, 2013 in New York City. (Photo by Astrid Stawiarz/Getty Images)
Stewart Butterfield, co-founder and chief executive officer of Slack Technologies Inc., smiles during a Bloomberg West television interview at the Vanity Fair 2015 New Establishment Summit in San Francisco, California, U.S., on Tuesday, Oct. 6, 2015. (Photographer: David Paul Morris/Bloomberg via Getty Images)
Snapchat CEO Evan Spiegel speaks onstage during 'Disrupting Information and Communication' at the Vanity Fair New Establishment Summit at Yerba Buena Center for the Arts on October 8, 2014 in San Francisco, California. (Photo by Michael Kovac/Getty Images for Vanity Fair)
Square CEO Jack Dorsey, right, poses with co-founder Jim McKelvey in front of the New York Stock Exchange before opening bell ceremonies, Thursday, Nov. 19, 2015. (AP Photo/Richard Drew)
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Nic Jammet, Jonathan Neman and Nathaniel Ru are the Co-Founders of SweetGreen in Washington, D.C. on October 17, 2011. Jane Black's November column is about SweetGreen and its efforts to stay true to its roots as it grows to be a regional and national chain. Nic Jammet, the young, charismatic co-founder, who is working hard to make sure that they still feature local products from small farms, even in wintertime. They have gone from 1 store in 2007 to 10 today, including several in the Philadelphia area. (Photo by Marvin Joseph/The Washington Post via Getty Images)
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(L-R) Casper Co-Founders & Chief Executive Officers T. Luke Sherwin, Jeff Chapin, Neil Parikh, and Philip Krim attend Casper's LA celebration at Blind Dragon on July 9, 2015 in West Hollywood, California. (Photo by Rachel Murray/Getty Images for Casper Sleep Inc.)