I have a friend who says he took something like a year and a half. I think it's because he had other characteristics that people read as feminine. Even now, more than five years in, he has a lot of qualities in his speech and hand gestures that people tend to interpret as "feminine," so they read him as gay. He complains about it sometimes but doesn't make any effort to change his patterns. I figure that it isn't important enough to him; he is obviously male (the beard helps), so why bother?
I guess my point is that if you do have such characteristics and want a better chance of being read as male, you might think it's worth your while to change those features. Then again, maybe not. But if you do work on those features, don't be surprised if it turns out to be wasted effort six months from now. T alone can work wonders if you wait long enough.
But some guys need more than just T; another thing that can help is attitude and confidence level. T might be the cake, but attitude can be the icing. If people call you she and you get embarrassed and sink into yourself, or if you are unsure of yourself, people can often read that--and they will tend to read it as female more often than not. And if someone calls you she and you don't correct that person, most people (including bystanders) will go along with that. The self-confidence should come over time, but you can help it along, too, with some positive self-talk.
I know it's hard to hear--believe me, I wanted my changes to come as soon as possible--but you have to give it time. And sometimes the inner work is as important (or almost as important) as the outer work.
