OK, I'm coming to a point where keeping myself a secret from my parents and my brother is really getting stressful. I'm tired of hiding from them. I want to come out, but I'm completely lost. I can't come up with a way to test the waters before coming out. I'm tired of them expecting me to be a guy, calling me a guy, insinuating I need to look more like a guy... (my dad really can't stand my hair. Just a little longer, and I can actually tie it back into a ponytail. I just have a few clumps up front that won't reach right now) In a way, these expectations are worse than my missing chest, or seeing the parts I shouldn't have....
I'm in the same boat. Sort of. My parents don't believe me when I tell them I'm their son, because I was "SUCH a feminine little girl", and was into dresses/dolls/princesses and all that jazz. I'm currently writing a long letter to them, filled with plenty of scientific and emotional evidence of my maleness, in the hope of convincing them to buy me a chest binder. Maybe you should try something similar? (Minus the chest binder part, of course)