If you have gay friends, family, mentors, this would be a good time to talk to them about how to handle the situation. Are you out to your parents and immediate family?
One thing I understand about coming out (I am not gay) is that it can be helpful to start small. That is, come out to someone who you know will be joyful and sympathetic first. You'll figure out what you want to say, and how to say it, in a more nurturing environment.
Or, as is true in a lot of other aspects of life, crawl before you run.