Now, five years later, Horrocks is debt-free and earns a six-figure income through her work-from-home voice-over job. Her advice to millennials similarly burdened with loans or credit card debt: “Do the math.”

“Stop spending on your [credit] cards,” she says. “Sit down. Be honest about what is going on with your finances, and then decide where you want to be. If you’re smart with your money now, you can right the ship and have a healthy financial future.”

Horrocks’ freelancing job gave her the means to “right the ship.” With 13 years of prior voice-acting experience, her Fiverr profile took off and she was able to leave her full-time corporate job.

She built a professional recording studio in her home. In an interview with Forbes, she says she works around 30 studio hours per week and makes about $15,000 each month.

To pay her debt, Horrocks first calculated everything she owed. “I sat down and took all my debts across all my five credit cards, as well as car loans. I made minimum payments all of them, then every single extra penny I had went onto the smallest debt,” she tells CNBC Make It.

When she paid off one loan or bill, she focused her payments on the next highest one. “The snowball eventually grew to where I was making massive payments and cleared the debt.”

Horrocks, who now owns Instant Voicemails, her own voice-messaging business, says it’s important to track your spending and create a budget. She believes the key to paying off her debt quickly was resolve.

“I took side jobs, freelanced and hustled with the best of them. I used coupons. I sold things I no longer needed. I learned new skills and I didn’t take vacations, go shopping or live beyond my means,” she says.

The hard work has paid off: “My credit score used to be nothing to smile at, but, after paying down all that debt, it is excellent. I have no trouble getting a mortgage now, and I have excellent credit cards that I use all the time to gain points, then pay off in full at the end of the month.”

Millennials who want to pay off their debt speedily can take Horrocks’ advice. They can also listen to Amber and Danny Masters, who aim to pay off $600,000 in debt in five years.

“It is tempting to bury your head in the sand and ignore the weight of your debt,” Danny tells CNBC Make It, “but you really have to lean into your situation to get a handle on it. The earlier you come to understand it, the less painful and more manageable it will be in the end.”

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