Well stop comparing urself with others, that's a start

By accepting your self as you're, all of us are equally human, we are just different.

That habit doesnt just come over a night, u have been programmed to feel that way over a series of indistinct events in your life. its simple to change if u give it time. what you have to do is, that u have to put urself in a life where u are psychologically rewarded for most of the random things that u do in your life. That is how u build self-esteem. dont ever keep a friend that keeps making a negative remark on every single thing that u do. and better yet befriend those people who appreciate and praise what u do... this is probably the no. 1 cause for loss of self-esteem and self importance. the simplest comment on your look, thought or deed could boost ur daily self-esteem and self importance. simple comments like u look cool today, you did well. doesnt matter how close u are wiht ur friend, if he/she is always making u feel like a shit you should dispose of him. if u dont. later on you will stop feeling like a shit cuz u will be the shit itself.