With her big personality and va-va-voom figure, Kate Upton has quickly become the antidote for faceless, stick-thin models. Coming from Carl's Jr. land, she's successfully managed to move into the high-fashion world, booking spreads in Vogue, Harper's Baazar, and Muse — while still owning her undeniable sex appeal. Favoring colorful and body-hugging dresses on and off the red carpet, the model knew how to work her best angles from the very beginning. Click ahead to see the Sports Illustrated Swimsuit Issue cover girl's style evolution.