Steve Madden fell in love with the shoe business in the 1970’s, when he sold platform shoes at a neighborhood store in Long Island, New York. That was in high school. About 15 years later, he struck out on his own, designing and selling shoes with a high-end look at affordable prices. As his business – and his ambitions — began to grow, he got involved in a securities fraud scheme and wound up serving two and-a-half years in prison. In 2005, he returned to Steve Madden, where he helped the company grow into a business valued at $3 billion. PLUS, for our postscript “How You Built That,” how Chris Dimino turned a school design project into the Keyboard Waffle Iron, which makes waffles in the shape of a computer keyboard.