Ex-Wall Street titan Sallie Krawcheck shares the worst money advice she’s ever heard

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Krawcheck onstage during TechCrunch Disrupt NY 2016

If you're looking for advice on what to do with your money, you can find thousands of articles on how to save, invest and plan for the future.

But some tips should be taken with a grain of salt.

For Sallie Krawcheck, co-founder and CEO of Ellevest and former Wall Street executive at Morgan Stanley and Citibank, the worst financial advice she has ever heard came from her ex-husband. When Krawcheck's younger brother graduated from college, her then-husband, an investment banker, told him not to bother investing and saving for retirement because he wasn't making enough money for it to matter. He assured the young man he could always start later.

"He didn't recognize the power of compounding," Krawcheck said at a recent Ellevest event in New York City. "If you begin early and ride the ups and downs of the market, by retirement the amount you have swamps that $1 you put in to start."

Compound interest allows any interest earned to then accrue interest on itself, so over time a small amount of money invested earlier will earn more than a large amount of money invested later. That's why it's so much easier to end up a millionaire if you start putting away cash in your 20s.

Krawcheck shares an example of how this works on the Ellevest blog. She writes:

Say you invest $100 today and earn 10 percent on it in the coming year; that's $10, which means you then have $110. If you earn that same 10 percent return the next year, you earn it on the $110. So you earn $11, not $10. Do it again, and the same 10 percent return earns you $12. And so on and so on. And over time, it adds up to a lot.

Krawcheck points out an important financial lesson that many fail to understand: It's never too early to begin investing.

"Even if you're thinking, 'I don't have a lot of money right now,' you need to save for future you," she says.

Even if you can only contribute $50 or $100, start there. Although entering the stock market might seem intimidating, it doesn't need to be. Krawcheck's Ellevest makes the investing process easy to follow and requires no minimum to open an account.

Here are a few more low-stress ways to start investing:

• Sign up for your employer's 401(k) plan and take full advantage of any company match, which essentially gives you free money.
• Contribute to an individual retirement account that offers tax benefits, like a Roth IRA or a traditional IRA.
• Use a micro-investing app like Acorns, which helps you begin by investing small amounts of your "spare change." The app rounds up your purchases to the nearest dollar and automatically puts your coins to work.
• Try other apps that aim to make investing simple and accessible.
• Consider automated investing services known as robo-advisors that can help you out no matter how much you have in the bank.
• Research low-cost index funds, which Warren Buffett recommends.

There's no guarantee that the market will perform in the future. Your returns will vary based on which accounts you choose, when you start investing and how much you contribute. Still, as Krawcheck reiterates, the earlier you start, the better.

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