After graduating from Princeton in 2002, Ellie Kemper moved to New York to try to make it as an actor. While she auditioned and performed improv comedy, she worked at the now-closed Crumbs Bake Shop on the Upper East Side, and learned a few things about lattes.
"I don't think it's around anymore? I know it's not around anymore, but it was a great cupcake shop while it lasted! I don't take credit for that, but I had something to do with it. I was serving the cupcakes," Kemper tells CNBC Make It. "I had the early shift, 6 a.m. to I guess 2 p.m., and I got kind of good at making lattes. I wouldn't say, I mean, I wasn't hired for my ability to make lattes, but I learned how to do it, and you'd be surprised how many people are angry when they're going in to get cupcakes. You'd think, 'Oh they'd be happy,' but no."
That description of her time behind the cupcake counter is a sharp representation of Kemper — fast paced, self-deprecating, humble, hilarious — as well as many of the characters she's played. Kemper got her big break when she landed a role on "The Office," playing the peppy Erin Hannon. She says she spent her first big paycheck from the show on two pizzas from Pizzeria Mozza.
Since then, Kemper has reached a level of success most actors only dream of, including her recent turn as the innocent but unstoppable title character in the "Unbreakable Kimmy Schmidt." This October, she's releasing a collection of essays, "My Squirrel Days," that looks back on growing up in St. Louis, quitting field hockey and her breaking into comedy.
Here, Kemper shares three things she says she's learned from working with comedy legends like Steve Carell and Tina Fey:
Kemper quickly saw that what made her co-stars great comedians, actors and people was their humility. This trait made them stand out and made people excited to work alongside them.
"Steve Carell, Tina Fey, Kristin Wiig — I feel like these are all people who are humble people, who work very hard and are kind," she says. "How lucky to be able to work with people like that?"
"It's important to persevere and to go after what you think is important to you," Kemper says, but she adds that there's another skill that's equally useful. "There is a very valuable lesson in knowing when to call it quits."
One chapter of Kemper's book follows her short-lived career on the college field hockey team. After a grueling first season, Kemper realized that she didn't have what it took to make it in sports. Her decision to stop playing field hockey would end up being key to her success, because it gave he the opportunity to pursue her passion — comedy.
"I thought I was really good, and then I got to college and I realized I'm not good. I'm fine, but I'm not good enough and time is limited and I'm going to shift my focus. I'm going to quit — I shouldn't say 'quit' — I'm going to stop being on the team now," says Kemper. "And that's when I started doing improv, and that's what led to me pursuing comedy."
She says her former field hockey coach came to her improv shows and sat in the first row.
Kemper says that while there's certainly no secret to success, the super-successful people she's worked with all work hard.
"The secret to most people's success is to work hard," says Kemper. "Because anyone you meet who is successful works hard."
And it doesn't stop when you're a household name. "I always have this fantasy, 'Oh the people at the top, they don't work as much anymore,'" says Kemper. "But every highly successful person I've met works very hard."
Like this story? Subscribe to CNBC Make It on YouTube!