A badass boss shares her playbook

May 6, 2014, 10:35 PM UTC

How Nasty Gal founder Sophia Amoruso went from being a shoplifter with bad credit to the CEO of a $100 million web sensation.

FORTUNE — “I’ve always had issues with following the rules, which has made Nasty Gal the only thing I’m capable of doing.” So says Sophia Amoruso in her new book, #Girlboss, but based on her success turning a shoplifting habit and an unconventional education into a $100 million tech company, don’t believe it.

We live in an era where chutzpah and high-speed Internet access (Amoruso has both) often trump a traditional business pedigree and a consulting internship. Rule-breaker CEOs seem to be the new normal, though in #Girlboss — part memoir, part management how-to guide — Amoruso ups the ante. The 30-year-old millionaire has gained fame and notoriety for her brand Nasty Gal, an edgy, sexy online women’s clothing store that she started building on eBay at age 22. The company’s hockey stick growth trend may be familiar in the tech world, but Amoruso’s road to internet fame is not that of your average Stanford-educated wunderkind.

In #Girlboss, which comes out on Tuesday, Amoruso tells a story of a quirky wild-child growing up in the ennui-inducing suburbs of Sacramento. From her inability to focus on school to her eventual decision to leave home and hitchhike around the West Coast, she addresses the highs and lows of her journey with an honesty that’s refreshing in a management memoir. In fact, the most valuable lessons Amoruso imparts aren’t about savvy business moves per se, but come from the moments when she makes a complete mess of business, for example compromising her credit by forgetting about a Victoria’s Secret card she signed up for just to get a $28 bra. Her wrecked credit score, however, became an asset later on. She learned how to manage her finances without relying on credit or loans, building Nasty Gal purely on cash and venture capital.

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Amoruso recounts her early days of fervent anti-capitalism — which led her to not only take up dumpster diving but also to rationalize a destructive shoplifting habit — and she discusses, with some zeal, being fired from a series of hourly wage jobs. (“Getting fired was always a big deal to me. It’s a bit like having someone break up with you.”) The Amoruso of #Girlboss is the kind of character that you likely would have wanted to befriend in high school, much to the chagrin of your anxious parents. And yet, from the get-go, it’s clear that even in her lowest moments, Amoruso was cunning. From selling a stack of stolen books for $200 on Amazon to refusing to shop in mainstream stores, her rebellious young adulthood turned out to be good preparation for entrepreneurship.

Shortly after dropping out of art school for photography, Amoruso launched a modest eBay store where she sold secondhand clothes, calling it Nasty Gal Vintage — a tribute to Betty Davis’ funk album of the same name. Amoruso’s book grows up from here. She recounts, with some teeth, the ins and outs of starting an online store while going up against catty eBay cliques. She logs hours digging through every item of clothing in thrift stores around the Bay Area and styling the better pieces to be sold online. “I was watching my auctions close, totaling $2,500,” Amoruso says. “I was making more in a week than I’d ever had in a month at my hourly jobs.” She also has real lessons for future entrepreneurs, like on the importance of smart hiring: In the early days she strived to stay true to the Nasty Gal brand, and fought to preserve the culture after the company exploded and moved to Los Angeles. Her tales of getting venture capital will be particularly entertaining to Silicon Valley folks.

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If Amoruso errs in her manual, it’s when she attempts to tackle the thorny topic of women in business. At its core, the book is a straight (though colorfully written) business memoir. To call it also a feminist business memoir diminishes its scope. In today’s post-Lean In culture, we’re more aware of how “female CEO” is used when a simple “CEO” would do. #Girlboss takes what might be a universally appealing story, and labels it girls-only, even though she’s likely trying to reclaim the term. To be fair, she does refer to the hardworking men in her organization as #DUDEBOSSes.

Amoruso’s swagger in #Girlboss is contagious. The book is a decent model for all the girls — nay, people — who don’t want to climb the traditional career ladder. Her path, though unconventional, might even inspire a couple of readers to try to heed her lessons and follow in her footsteps. But if there’s one real takeaway from reading Amoruso, is that a pre-packaged rulebook for business success no longer exists.