"Sometimes people would be particularly nasty and rip up my business card in my face," she said.
And then one day, she had that "a-ha" moment that would forever change her life, sparked by a troublesome pair of cream-colored pants.
"Every time I put them on you could see the thong," she said. "You could see some cellulite on the back of my thighs and I thought, 'what am I supposed to wear under this?' So I cut the feet out of my pantyhose. My rear looked firm. My cellulite had been smoothed out, but they rolled up my legs all night."
Blakely said if she could figure out a way to keep them comfortably below the knee, she would have a homerun product for women. So with $5,000 she had saved up from her fax machine sales, she started cold calling hosiery mills, but was turned away time and again until finally a bite.
"One guy called me after I made the rounds, [and said] that 'I have decided to make your crazy idea,'" Blakely said. "I found out he ran it by his daughters over dinner and they said, 'Dad, help this girl make it. It's a good idea.'"
She decided on the name "Spanx," she said, because her product was "all about the butt" and "nobody forgot it."
Her first coup was a single sales pocket in the hosiery department at Nieman Marcus. When she saw her product next to the Donna Karan and Calvin Klein, Blakely said, "I just sat on the floor and wept."
Just two months into the business, Blakely got a call from Oprah Winfrey, who anointed the Spanx footless pantyhose as one of her "Favorite Things" of 2000, and afterwards sales exploded.
"The orders started coming in all day, all night," Blakely said. "I had to have friends come over and help me ship them out. I became very good friends with the people at Mailboxes, Etc."
Her one-woman business run out of her apartment is now a 90-person, billion-dollar company.
"I manifested almost everything that has happened to me in my life," said Blakely, who credits much of her success to visualization and the power of thought.
After making the Forbes billionaires list, Blakely said she was humbled and honored, and continued to recognize a sense of gratitude for being born a woman in the United States.
"I had a lot to do with my destiny, but I didn't have a lot to do with where I was born," Blakely said. "And I'm so grateful for that."
Her success has inspired a program called "Leg Up," in which she spotlights and supports other female entrepreneurs just starting out.
"It's my way to pay the Oprah moment forward," she said. "Because I think women helping women in business is good karma."
Through her charitable foundation, she has contributed over $1 million to causes that support women. Blakely said she sees Spanx as a step to achieving her greater life-long goal of helping women everywhere fulfill their own potential, and she's excited to make a major impact.
"When I cut the feet out of my pantyhose, I thought, oh, this is interesting," she said, "This is how I get there."