U.S. Olympic gymnast Laurie Hernandez is only 19 but she's already mastered these 3 financial skills

World champion gymnast, Laurie Hernandez, training to compete in next year's games in Tokyo.

Laurie Hernandez is only 19, but she's already a two-time Olympic medalist and New York Times bestselling author — and that just scratches the surface of all her accomplishments.

"There's definitely been a lot that's happened since the 2016 Olympics, but it's a lot that I had always hoped for as a little kid," Hernandez tells CNBC Make It.

Since the Rio 2016 Summer Olympics, where she won a gold medal in the team event and silver on the balance beam, Hernandez has kept busy. She released two books: a memoir, "I Got This: To Gold and Beyond," and a children's book, "She's Got This." Hernandez also won season 23 of "Dancing with the Stars" and co-hosted the first season of "American Ninja Warrior Junior."

More recently, Hernandez partnered with eye-care company Alcon for a new campaign called "Eye Can, Eye Will." She earned national media attention during the Rio Olympics for her habit of whispering "I got this" to herself, and she hopes others create their own words of encouragement with the Mantra Maker at

The 19-year-old isn't just a master of mantras, she's also very thoughtful about her finances. She knows the importance of saving for retirement early, even though she says "I don't think I'm going to be retiring any time soon."

While winning an Olympic gold medal or Mirrorball trophy may be out of reach for the majority of Americans, you can easily follow Hernadez's three key financial tips below.

1. Carry cash in your wallet

It may come as a shock that Hernandez, a Gen Zer, carries cash in her wallet.

She primarily relies on Apple Pay, but a couple of years ago a friend encouraged her to start carrying cash as a safety net. "You never know," Hernandez says of when you may need to use cash.

If you're someone who's tempted to overspend with a credit card or mobile payment app, paying with cash can be a good alternative. After all, cash is tangible — you can't spend what you don't have.

2. Learn how to budget

"Learning how to properly spend and budget has been a really important lesson," Hernandez says, who admits she loves to go shopping with her sister.

She's right — and it's a skill that teens shouldn't be reluctant to learn. If you can get a handle on your finances when you're young, you can set yourself up for success later in life. Creating a budget doesn't have to be overly complicated. You just need to have a sense of your monthly income versus your monthly expenses and be careful not to overspend or skip saving for retirement.

Hernandez credits her parents for being "a really big help" teaching her to manage her money.

3. Invest in a retirement fund

Hernandez says saving for retirement is one of her financial goals. The importance of setting aside money for the future "is something that's been stressed to me by my parents."

This is smart advice from someone so early in their financial life. Hernandez agrees it's never too early to start investing in a retirement fund.

She has a SEP-IRA (Simplified Employee Pension-Individual Retirement Account) with Vanguard, which is for people who are self-employed, own a business, employ others or earn freelance income.

While you may not meet the requirements for a SEP-IRA, there are some other ways you can start investing on your own, such as a high-yield savings account or ROTH IRA. And, many employers offer 401(k) plans where they match a certain percentage of your contribution (on average 4.7%).

"Budgeting and saving is my biggest thing," Hernandez says.

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