Coming out at age 22.?

I am 22, female, and considering coming out. My family are good people, but extremely phobic in general, so I have been too afraid to come out while I lived at home. I have been surprised that no one has figured it out, considering that I don't date and have a clic butch personality. Now that I live on my own I really want to, but I don't know how to go about it without insulting anyone. Suggestions?