The founder of the subversive fashion brand explains her improbable rise and her ‘no assholes’ leadership style.

“I never expected to end up the CEO of what’s now a corporation,” NastyGal founder Sophia Amoruso said today at South by Southwest before a mainstage audience. “It was my full intent as a teenager to smash capitalism and eat dumpster food. It’s been one hell of a ride.”

In a wide-ranging interview with Inc. Senior Writer Christine Lagorio-Chafkin, Amoruso talked about her improbable rise to creating and leading an innovative fashion retailer and the keys to her success. Among them: trust in her aesthetic instincts, a natural affinity for social media, and knowing how to surround herself with the right people.

Angst and Anarchism

After launching as an eBay store selling vintage items, NastyGal became a standalone ecommerce destination in 2007 and quickly pivoted from selling vintage to selling subversively sexy new clothing to 18-to-24-year-old city girls, Amoruso explained. By 2011, the company collected $24 million in revenue, and that number reached a reported $100 million in 2012, landing Amoruso on Inc.’s 2013 30 Under 30 List.

Before all that, she was “a pretty angsty teenager who frequented anarchist book fairs,” she said. Her first job was as a Subway Sandwich Artist. Other jobs included selling stolen books on Amazon and working the security desk at a San Francisco art academy. During that last job, she spent a lot of time on MySpace, the reigning social network at the time, and noticed a lot of people promoting their eBay stores selling vintage items.

“I could do that,” she thought. At the time, she was 22 years old and wore nothing but vintage clothing herself. She knew where to buy good stuff at lower prices than her would-be competitors, and realized she had a good sense for what would sell and how much to charge.

Talk to Them Where They Are

Through Myspace and eventually other emerging social-media channels, she was able to amass a large following at zero cost. “What people pay for on Facebook today I figured out how to do for free,” she said. “I had 60,000 friends on MySpace.”

“I grew up on the Internet, and it seemed like the natural thing to do,” she added. Customer service, never her strong suit in traditional retail jobs, became another benefit of Amoruso’s early social-media strategy. “It was easy for me in my bathrobe to provide really great customer service. As an introvert it’s really much easier to do than when standing in a retail store.”

Don’t Tolerate Assholes

Today Amoruso is the boss of 300 employees in Los Angeles. “Day by day, week by week,” she watched her company grow and developed as a manager simply by being closely involved at every level, because she didn’t have co-founders. Through experience she learned, however, that “there are some things that to get it right, you can’t control everything.”

She learned to “hire people and trust them,” she said. “I’m really good at hiring good people. If they want to work for a female-led company that’s venture-backed, the opportunity here is way cooler than that.” She looks instead for people who understand that NastyGal is building a unique brand that disrupts the way sex appeal is used to market to women.

As a manager, she follows a strict “no assholes” policy. “I have fired someone on the spot for being an asshole,” she said. “It’s an office full of girls, and no one is bitchy. It’s just not OK.”

What’s Next

Amoruso has written a book, #GirlBoss, that talks about her leadership style and will hit stores later this year.

In the next year, NastyGal has its sights on a move from being a retailer to a full fashion brand. Amoruso plans to launch a line of shoes, clothing, lingerie, swimwear, and home design.

A physical retail store is planned to follow that. Amoruso is seeking to bring her “community into the store, bring our tech into the stores. Being online first, we can do that in a way that others can’t. Most retailers are bogged down with legacy systems that will take them five years to replace.”