Much of Dick Costolo's professional track record is impressive: In June 2007, he sold his company FeedBurner to Google for a reported $100 million. And from 2010 to 2015, Costolo was CEO of Twitter. In 2013, he took the social media company public.
But some of his early career decisions seem to make less sense when you think of his corporate success.
Costolo graduated in 1985 from the University of Michigan with a major in computer science. But he turned down computer programmer job offers to move to Chicago and try to make it in improv. His goal was to appear on NBC's "Saturday Night Live."
He never made it as a professional comedian.
Still, Costolo says his time in Chicago studying improv was extremely valuable.
And that life experience informs his own best advice for young people who are trying to figure out what to do with their lives: Don't do what you are supposed to do, Costolo tells CNBC Make It.
"First of all, there is extraordinary pressure on students to come out of college sort of knowing what they're supposed to do," says Costolo. "I gave the commencement speech at the University Michigan in 2013 and I specifically told them, 'Don't do that — don't do what you think you're supposed to do.'
"Instead, take risks. Take big chances," he says. "The younger you are, the more risks you can take. You've got fewer responsibilities and probably don't have a mortgage or even you know kids or dogs or cats yet."
Follow your passions, says the ex-Twitter CEO, because it is easier to recover from a stumble when you are doing what you love.
"Take courageous risks. Take big risks. Pursue the things you want to pursue because when you when you're doing what you love and things go wrong — as they inevitably do — if you're doing what you love, you'll be you become resilient and you figure out how to move on," says Costolo. "And if you're instead doing what you think you're supposed to do and things go wrong — as they inevitably will — then you end up sort of stuck there frozen on the stage of your own life wondering what's supposed to happen next."
Every time Costolo took a big risk, it was worth it, he says.
"[W]hether it was leaving the University of Michigan without a job and going to Chicago to try to get into Second City and do improv comedy, or when I just picked up and moved out west without having any plans just before I ended up going to Twitter," says Costolo, who in 2009 moved to Marin, California to escape Chicago's harsh summers and winters.
"Those things that always paid off, whether they were immediate payoffs or or down the road payoffs."
For instance, even though Costolo didn't end up a comedian, the skills he learned studying improv in Chicago helped him be a better leader.
"I wouldn't trade the years I spent in Chicago doing improv comedy and being extremely poor for anything, because those those skills turned out to be extraordinarily helpful later in life when I'm leading a company and people ask you on the spot questions," says Costolo.
"First of all, when you're an improviser, the first thing you learn — and you learn very quickly — is to listen," says Costolo. Because if you go into it with an idea already in your head, when your fellow comedians take the scene in a different direction, that idea that seemed so funny originally is "just going to fall flat," he says. "You see it time after time. It doesn't work at all."
Instead, improv comedians have to take in what their teammates are saying and respond accordingly.
"One of the rules in improv is, 'yes and...' — basically accepting whatever they initiate and then taking the ball and running with it. It makes the scene a lot more fun.
"It's no surprise that turns out to be a great way of thinking about business too," says Costolo.
As a leader or manager, it's an important part of decision making to listen to feedback from your employees rather than relying on preconceived notions.
"If you don't listen, you learn this in improv and it's true in business, if you don't listen, you can't communicate," says Costolo.
Other odd jobs Costolo held taught him valuable leadership lessons too. Checking coats at a Chicago nightclub, Limelight, taught him humility, for example.
Costolo remembers a college friend came into the club and checked his coat. "I'm behind the counter and you could — he didn't say it at the time — but he sort of gave me this look of like, 'Dude, what happened? Where did you go wrong?'" says Costolo.
"All those things, I think, teach you humility," says Costolo. "Irrespective of what your actual day-to-day job is, people have the same sort of hopes and dreams irrespective of their role in the company or their day to day function."
Even checking coats can be a step on the path to self-made millionaire and Twitter CEO. Costolo is proof.
"You just learn that everyone chooses their own path and doesn't necessarily do what they're supposed to do, but it's fun to take risks," he says. "It can be hard to take those risks, but fun."
Like this story? Like CNBC Make It on Facebook.