At the risk of stepping far over my boundaries...
Your version of masculinity is innate. There are ways that you can manipulate gestures, mannerisms, speech patterns, etc to emulate an idea of "male" but those things aren't inherent to all cis males.
If you are confident and poised in your brand of masculinity, there is no question as to whether or not that is "male" because it is you, how could it not be?
cis men are as variant in expression, mannerisms, gestures, speech patterns, sensitivity, etc. as any other human being. They may question if they are as much a "man" as the lumberjack they are standing next to but the quality of their maleness is not in question based on how they put their shirt on.
My point is this: humans gravitate toward confidence and authenticity. We like other people that are centered, approachable, true, and kind. If you put on your shirt by standing in the neck hole and pulling it up over your waist people aren't thinking if that's a guy thing to do or not, they think you are being weird, which you kind of are, but it's all good. You are who you are. People will connect with that more than they will with you being overly attentive to your every gesture -- if people don't know why you are being so calculated they tend to read it incorrectly as your hiding something or somehow not being who you really are.
If you move from the core belief that you are a man (or however you identify) you feel confident and at peace with it, then everything you do is reasonably what men do... because you are one and your doing it... it's a little bit of circular logic but still relevant, IMO.
I'm just sayin'.