You change! You stop looking at the bad and start looking at the good, stop trying to change things you can't change and start accepting yourself, and if you can change something go for it! You're limits are the ones you give yourself, start loving yourself for how and who you are, because when you love yourself everyone else follows after, start being positive, shoot, I love you! :) so stop worrying about what others think about you, because those who mind don't matter and those who matter don't mind!
There must be a reason for this? correct? You need to think about why you hate your self. then realize that things happen and you cant tear your self apart when you get upset. Think about all the good things you can do.
You take a look at why. Then you think about all of the fantastic, interesting, beautiful things about you. Think of all of the people who love you. All of the lives you've touched permanently. Think about all of the people who need you and care about you. Think about the people who you will know and love, and who will come to know and love you in the future. There isn't much to hate.