Ugh, another shy person. I'm sorry, I really hate them. Anyway.. If you really want to overcome being shy then envision who you want to be. Is that person loud, fearless, or both? How would she react to this, and that? After a while of that, try to slowly act like that person, and you will become that person. Therefore, not being shy!
Step up: meet new people, practice speaking in front of other people (try starting off in front of your friends and people you know), and try to have a good appearance and attitude. People will enjoy a smile!
I tended bar . . . Obviously that isn't the best solution for you. But perhaps putting yourself in situations outside your comfort zone (that are not dangerous, illegal or immoral) would help. Like Karaoke . . .
Picture yourself through the eyes of other people. If you were around someone shy and uptight, wouldn't that make you even MORE aware of them and less comfortable around them? Wouldn't you rather that they talk louder or more often, or walk over and give you a high five? It would make you feel more comfortable. So act the way you would want others to act around you, and you'll be just fine!