I used to be very self conscious and shy. I'm now out going and really don't care what people think of me. Here are my tips:

-join something you enjoy that makes you feel good (I did kickboxing and pole dancing)
-whenever you start to wonder what someone is thinking about you, redirect your attention to what you are doing.
-go to therapy to build yourself up.
-hang around with people who build you up.
-remember it really doesn't matter what anyone thinks of you. When life is over, what will be important?

Its completely doable and freeing.