I think this is some really good advice.
http://tranifesto.com/2011/10/24/ask-matt-outing-yourself-for-the-comfort-of-others/ A reader writes: “I’m a 22-year-old trans guy just starting to feel my transition is mostly behind me. I’ve been perceived as male 100 percent of the time for maybe six months now, and I am semi-stealth. I had a strange experience the other day that raised a lot of questions for me about openness, visibility and disclosure.
“I was riding in an elevator with a woman. She made some joking small-talk remark to me, and when she spoke and looked at me I guessed she was probably trans (though of course it’s impossible to know for sure). It’s hard to explain why, but in the moment the thought passed through my mind, I felt she could tell I was thinking it, pegged me as a young cis guy, and became uncomfortable. I tried to give her an extra-friendly smile, but she abruptly turned away. I struggled to think of something to say, but I found myself at a loss, and then she hurried out of the elevator without further comment.