Things like this are hard, because I'm sure that when you see someone do something cool you get the urge to lie about yourself just so you fit in. Best thing to do, is to just don't be afraid to express your own opinion, when someone sais something and you think something different, say it, say how you feel no matter if you fit in or not, you need to find the group of people who accept you for who you are, not the people who accept you because you are like them. So you can start by looking at people's personalities also, like find the people that you see have things in common with you, so when it comes to being yourself, it's not as hard as with someone who does not have nothing in common with you, so you don't have that fear of not being accepted.
I think you should stop thinking what other people think about you. If you are constantly worrying about what they think about you, they'll never really know you. & they're likely to begin to like you for someone you're really not. It wouldn't be very nice if they started liking you for one thing, and then they discover it's not really your true self. Just don't worry about they think, and you'll begin to love yourself more too (:
You will find with age you care less about what people around you think, and more about key important people in your life. The funny thing is, the people in your school, after school you are not really going to see these people again, and all the opinions they had, are of no consequence.
Don't listen to others. It doesn't matter what other people think! Hang with people that are like you. For example, try to hang with kids that have similar intrests. It is not healthy to be some one your not. You'll be a lot more happier with yourself too. Goodluck! =)
What if the group of people that I hang out with are like me, but I'm too shy to open up?