Anoni is right about stepping out of your comfort zone, but you don't have to do it in one huge go. Small steps at a time, testing yourself here and there, and building confidence in ways you feel comfortable are ways that you can work on becoming a little more outward. I consider myself horridly introverted, but for me, just taking small steps outside my comfort zone, one at a time, made a pretty big difference. There /are/ comfortable ways to exceed your comfort zone, believe it or not, it's just a matter of finding the more fun ways of testing yourself. Over time you'll notice that the steps you've taken previously will be a breeze ^^