I like this girl,but she friendly to everyone.how I am supposed to tell her that I like her very much?

Hi I am going to tell you from a girls point of view, and yes I am also very friendly to everyone. Just tell her that you really care about her and want more than just a friendship with her if that is what you want. Depending on if she has droped you hints that she likes you, then she will say yes. There is no other way to say it just tell her how you feel, and soon you will see the benefits of doing so. Just because she is friendly to everyone does not mean that she does not have a special place for you. So long as it does not go beyond friendly.
Also she just might try to get you jealous by flirting with other men to get you to step up and tell her how you feel, we have a tendency to do this. Sorry