I probably didn't pick the best approach to tell my friend's that I'm gay either... I mean, who tells their friends that you're gay when everyone is studying together for an organic exam the next day?
But no, seriously. We hit up the topics of sex, relationships, women, guys, etc... then I just told 2 friends, then another 2 and some more friends.
Or simply sit down with a few friends that you trust and just let it out so they can hear. Don't be surprised if none of them believe you. It took roughly half an hour for my friends to believe me... there was just too much laughter.