well what helped me, is trying new things, like crazy hair styles or clothes, or funny locker decorations or whatever; things that you like that may be a little strange or unorthodox. if your friends are truly your friends they’ll love you no matter what. . . so then you shouldnt pay attention to what anyone else says. ;)
plus, if people know that you are your own person and not afraid to show it, they will respect you for that.

most of the time, not caring about what other people think is only a matter of finding your own unique style and sticking to it.
hope that helps ^__

-bree