Lauryn Williams had already made Olympic history by the time she accepted an internship that paid her just $12 an hour. 

The former track star, who was 30 years old at the time, was the first American woman — and sixth person ever — to medal at both the Summer and Winter Olympic Games. But with her athletic career behind her, Williams wanted to figure out how she would spend the rest of her life. 

"I had some recognition about the fact that I was behind the ball because I was 30 years old and just starting, whereas I had friends who were already doctors and lawyers and well into their careers," she told CNBC Make It. "I spent all of my 20s competing, so I felt kind of insecure that I didn't have any real work knowledge."

Williams, who majored in finance during the time she spent at the University of Miami, had a few less-than-ideal run-ins with financial advisors during her career while trying to figure out how to best manage the more than $200,000 she was being paid by Nike each year as a sponsored athlete. In her post-athletics life, she decided she wanted to help people make smart decisions with their money. 

"Basically, I did a Google search after having a second financial advisor that didn't work out and found CFP coursework," she said. "I enrolled in it blindly, simply because I wanted to better understand finances for myself."

Through her coursework, she found the office where she applied to be an intern. Though she had initially been told the office wasn't hiring, the owner decided to bring her onboard after hearing about her impressive background. 

"I had a good conversation with her, she was a stay at home mom who decided to start her own firm," Williams says. "It was a perfect fit for me." 

After two unsuccessful attempts at passing the CFP exam, Williams finally passed in 2017. Now 40, she is a CFP Board Ambassador and dedicates her time to giving financial education and planning to athletes and young professionals through her fee-only firm Worth Winning.  

Williams sat down with CNBC Make It to discuss the financial lives of Olympians, the challenge of becoming a certified financial planner and how she found herself winning an Olympic bobsled medal to go along with her track and field gold.

What are some common misconceptions about Olympians and their earning potential? 

I think there's the misconception that once you've got that Olympic gold medal, you've got it in the bag and are going to be set for life. From a sponsorship standpoint, I've had multiple gold medal-winning athletes as clients who didn't compete in "premiere" sports and weren't clearing $100,000 a year after all was said and done. 

Olympic sports in general are kind of like the world: You have a 1% that is earning very, very well and has more money than they will ever need, you have the vast majority of people who are getting by, and you have the people who are struggling. 

There are the people that you would call the headliners of the Olympic games that are in commercials and those sorts of things, who are going to be able to retire and never work again after if they organize their finances accordingly. But the vast majority of people are going to need to work. 

I had a $200,000-a-year contract, but I'm working now. What people don't realize, even with a $200,000 income, is that your agent takes 20% of that. And then you have to pay taxes as well. The money doesn't go quite as far as people think it does, even though it was a pretty good living for a 20-year-old! 

I had a 10 year career, so it set me up better than the average person by the time I was 30. But it also didn't give me the income to kick my feet up forever and never have to do anything again. 

What was harder, training for the Olympics or studying for your CFP exam? 

The exam is unbelievable. I actually failed the exam twice before I passed it. That was where I had to use my athletic perseverance. It was like, "Let me figure out how to do this. I know I'm smart enough to pass this exam. What am I not doing right?" It was very similar to thoughts I had [as an athlete like] "How do I need to train differently so that I can win this race?"

That was the kind of mentality that I took on. It was very frustrating, because I'd always been pretty good at school, so I didn't think it was gonna be hard. I was like, "I already find this coursework interesting. I've learned this stuff. Why am I having such a hard time passing the exam?" But I think it's because they want to make sure that people who pass that exam have really gone through the rigor and really do understand the content. 

What inspired you to take up bobsled ahead of the Sochi Olympics? 

I was injured in 2013. It was my last season of track and field, but I already knew that I was going to be done at the end of that year. I could have tried a few more years, but for me it was not about just staying in the mix, it was about either being at the top or not participating at all. I ended up getting injured during that season, and so I wasn't able to compete in the way that I wanted to. 

I ran into a girl in the airport who I knew had tried bobsled previously and I asked her to tell me about it. She was like, "Lauryn, you should try it, it's so amazing. It's the Olympic year!" And so I jumped into bobsled with my track and field injury, not knowing if I'd be able to do it either. But it turns out that the position that I had to get into to push a bobsled was a position that actually didn't hurt or affect my injury at all. 

I found bobsled as it was the last opportunity to try out before they were in the Official Olympic process. I stumbled on it at just the right time. 

I didn't have any financial motivations whatsoever. I didn't know how you made money in bobsled or if you made money in bobsled. I think that now, athletes are in the mindset of "How can I parlay the media attention that I'll get from this into something else?" But it was all very last minute. I tried out in July and the Olympics were the following February. 

The news coverage came, but the sponsors didn't. I made $80,000 the year I became the first American woman to medal in the Summer and Winter Olympics. 

There's this misconception that because I'm the first to do this thing — and still no one else has done it — that I'm booked all year long for speaking engagements. I get things here or there, but I can't make a living from it. And the last American to do it was in 1932, so it's not like I have him to compete against! 

What's the one piece of financial advice everyone should hear? 

Automate your savings. I don't care if it's just $5 a month, if you're in the broke boat and just trying to make ends meet as an athlete. Just automating it and putting something aside will create a habit of prioritizing yourself. And those savings will come in handy at some point when you need them. 

Also, get a retirement account open. Doesn't matter what kind, doesn't matter what you're putting into it, just put something into a retirement account. You're creating a habit that says "I am in touch with the fact that I will have a future" and your future self will thank you for it. The best thing I did during my time as an athlete was to open a retirement account. 

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