How No. 1 New York Times best-selling author Jen Sincero went from $28,000 a year to 'making seven figures'

Before Jen Sincero made a name for herself as a success coach and became a New York Times best-selling author with her book "You Are a Badass," she was struggling to make ends meet as a freelance writer.

"I was probably making about $28,000 a year on average," the now 53-year-old success coach and author tells CNBC Make It. "I was living in Venice Beach, California, in a teeny, tiny, crappy apartment."

And, until eight years ago, Sincero had nothing in savings.

"I knew precisely zero things about making money until I was in my forties. My forties!" she writes in her 2017 follow-up, "You Are a Badass at Making Money." "That's the age when most people possess things like houses and college funds for their kids and an understanding of how the Dow Jones works."

It was around this time when she "just finally woke up," she writes, and made the decision to "get over my fear and loathing of money and figure out how to make some."

The first thing she changed was her mindset.

If you want to build wealth, you have to start by telling yourself it's OK, Sincero says: "One of the biggest obstacles to making lots of money is not a lack of good ideas or opportunities or time, or that we're too slovenly or stupid. It's that we refuse to give ourselves permission to become rich."

After all, it can feel awkward to admit that you have that ambition — but it's necessary.

You have to agree "to get really, really, really uncomfortable. Over and over again," writes Sincero. "You must not only admit to desiring, and commit to creating, wealth but, most important, you must allow yourself to do so."

Changing her mindset was a good first step, but Sincero also shifted her focus to earning, she tells Make It. "If it wasn't going to make me money, I didn't do it."

"I went about it the same way you would if you were losing weight," she continues. "You wouldn't fill your house with crappy, fattening food, you wouldn't hang out with lazy people — you'd get your butt to the gym, you'd buy workout gear, you'd eat healthy food, you'd hang out with people who are in that mode.

"So that's what I did: If if wasn't making me money, I wasn't interested in it. And I really worked hard and focused on all the things that I knew would increase my income."

You can't just work hard, she emphasizes. You have to be smart and efficient. "I was working my butt off as a freelance writer making zero dollars," she says. "I make way more money now and I work way less, so that's a big fat lie that you've got to work hard all the time if you want to make a lot of money."

The key is to find "a viable income stream."

Sincero stopped freelancing and set up an online business helping entrepreneurs write and sell book proposals. Within three months, "I tripled my income," she says. And that was just the beginning.

Having experience informally coaching female entrepreneurs, Sincero started working as a "success coach" around 2008. Over the next several years, her business took off and she worked with hundreds of clients.

Her achievements as a coach led to speaking engagement opportunities and, eventually, a book deal.

Her first book, "You Are a Badass," was published in April 2013 and became a No. 1 New York Times best-seller. She has since published "You Are a Badass at Making Money," another New York Times best-seller, in 2017, and, most recently, "You Are a Badass Every Day" in 2018. The three books, combined, have sold over five million copies.

Today, Sincero is "making seven figures as a success coach and author," she writes in "You Are a Badass at Making Money," though, through her representatives, she declined to share more specifics. And she has learned that "a healthy desire for wealth is not greed. It's a desire for life."

Because, she writes, at the end of the day, "money gives you freedom and options."

Sincero recently bought her first home, which she's now "renovating the crap out of," she tells Make It. Plus, she's "driving a new car and buying the toilet paper I want to buy and the toothpaste I want to buy and traveling first class and giving a ton of money away and treating the people I love to stuff. It feels really nice."

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