We’ve all wished we could be someone else, whether it’s just polishing a few dull spots in our personality or fully rewriting the story of our lives, Jay Gatsby-style. If you're a procrastinator, you may have wished you could be more productive; if you're gloomy, you may have hoped you could be more optimistic; if you're shy, you may have longed to be the life of the party. Changing your core personality traits (e.g., introversion) is difficult. But what you can change is your behavior. It's never too late to do what you want to do, and with a little sweat and a little luck, you can break out of old patterns and be just who you want to be.