Don't let being transgender make you think you have to fit into a cookie-cutter idea of what a man is or should be.
You like wearing eyeliner? Wear it.
You like having long hair? You might get "ma'amed", but so what? It doesn't mean you -are- a ma'am.
You speak with flamboyant expressiveness? Go for it! Don't try to force yourself into speaking in monotone just to be more masculine.
There is really no such thing as "passing" anyway because that implies deception rather than expression. We can sometimes get too caught up in "proving" our gender to others when there is absolutely no need to do so. It's not something that can be proven by how flat your chest appears or how deep your voice is. It's in your brain, your soul, your personality, and your identity; being overly-conscious of yourself and trying too hard to prove it with your body/mannerisms is a recipe for disaster.
If you feel like having a flat chest or deep voice or anything else helps you express who you are inside, then go for it! But if you're only doing it to try to convince others of a truth that--in the grand scheme of things--only you need to be convinced of, you'll just be swapping one misery for another.
Now I am well-aware of the reality. It hurts when people see you in a way that is different than the way you see yourself. Believe me, I get that. But investing your time in trying to get others' perception of you to line up with your own is so much less important than investing your time in living your life as you please, doing what makes you happy, and expressing your true self. At the end, only a few people will matter to you, and those will be the ones that really did see you the way you did. Those people will be magical.
TLDR: Care less about what others think. Be you. Be a hyper-masculine, beer-chugging, sports-watching guy; be an artsy, indie-movie-making, skinny-jean-wearing guy; be a fabulous, theatrical, sophisticated guy; be anything in between. There are so many different type of men in the world. What kind of man are you, truly? Whoever he is, be him and no one else. Don't let ->-bleeped-<- limit you.