The CEO of S'well says this Harvard assignment makes her more productive

S'well CEO Sarah Kauss on how journaling made her a better entrepreneur

When Sarah Kauss was attending Harvard Business School in the early 2000s, a professor gave her class an interesting assignment: The students were to keep a daily journal of their thoughts and ideas.

"At the time, I thought it was a bit of a funny thing to do," Kauss tells CNBC Make It, at CNBC's iConic conference in New York, "but now I find it a really valuable professional exercise."

Kauss, founder and CEO of S'well, which makes fashionable, reusable water bottles, continued with the exercise after graduation. Journaling, she says, helped her realize her goals and grow as an entrepreneur.

Sarah Kauss, CEO & Founder of S'well.
David A. Grogan | CNBC

"I actually keep a five year journal," she says. "So five years ago today, four years ago today — on the same page."

She's tracked her progress along the journey from quitting her full-time job in real estate to start her company in 2010, to hitting $10 million in revenue in 2014, to growing that to $100 million in 2016.

"It's really hard to think of what you're looking to do when you're a busy person," she says. "It's hard to get up on the balcony of your life and look down on it."

To pause, gather her thoughts and reflect on her life, the CEO takes a few minutes either at the start or end of each day to write down her thoughts.

The journal helps her "understand where creativity comes from," puts things in perspective and tracks her motivations. The exercise can be especially helpful for people who are looking to switch jobs or even careers, Kauss says.

Ask yourself "What have I appreciated in my career?" and "What do I like doing?" Next, ask yourself, "What is it that I'm seeking to change? What is it that I'm looking to do?"

The more specific you get, the CEO says, the better.

It's really hard to think of what you're looking to do when you're a busy person.
Sarah Kauss
S'well founder and CEO

Kauss isn't the only one to recommend journaling. Tony Robbins, bestselling author and entrepreneur, says that keeping a written journal is one of a few ways to be more productive. Daymond John, entrepreneur and co-host of ABC's "Shark Tank," says journaling has helped him become more successful.

In journaling, you could keep a list of your ideas, short-term and long-term goals or things you are grateful for.

Keeping a journal can help you keep track of your ideas, goals and what motivates you, Kauss says.
Peter Rutherhagen/Getty Images

A widely cited study by UCLA and the University of Miami found that people who wrote down what they were grateful for on a weekly basis were more cheerful and optimistic about the upcoming week than those who didn't. They also had fewer doctors visits and missed fewer days of work.

"For me personally [journaling] has really helped pushed me to become an entrepreneur," she says. "It really makes me realize where we've come so far and how much we still have to do."

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

Video by Richard Washingon.

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