I always joke and say I want to invent a comfortable stiletto and then retire.

When I was growing up, my dad would encourage my brother and I to fail. We would be sitting at the dinner table and he would ask, 'So what did you guys fail at this week?' If we didn't have something to contribute, he would be disappointed. When I did fail at something, he'd high-five me. What I didn't realize at the time was that he was completely reframing my definition of failure at a young age. To me, failure means not trying; failure isn't the outcome. If I have to look at myself in the mirror and say, 'I didn't try that because I was scared,' that is failure.

If somebody can do something 80 percent as good as you think you would have done it yourself, then you've got to let it go.

We don't have the luxury of time. We spend more because of how we live, but it's important to be with our family and friends.

Everything about my journey to get Spanx off the ground entailed me having to be a salesperson - from going to the hosiery mills to get a prototype made to calling Saks Fifth Avenue and Neiman Marcus. I had to position myself to get five minutes in the door with buyers.

Don't let what you don't know scare you, because it can become your greatest asset.

I knew that I wanted to start my own business. I knew that I wanted to work for myself. I was no stranger to the word no. You just have to keep going.