Not to talk badly about being young, but do remember that older people tend to be more mature and better at being friends. At least, that's my impression.
And I agree with iKero about staying true to yourself. As an example, I burp in public without hiding it. If anyone dislikes this a lot, they're not fit to be a friend of mine because I often do obscene jokes and such. They may be a great person but we're just not good together. C'est la vie.