In my case, being bigender/genderfluid, it’s that I experience dysphoria. Gender isn’t your presentation. A cis butch lesbian or tomboy is still a woman even though they might wear masculine clothing. Just like a cis man in a skirt is still a man.
Like, here’s where I see it being a bit confusing for some people. My best friend likes to wear exclusively sports bras because she wore them a lot in the past and now seeing her chest in a more normal bra just looks odd to her. She is still cis, her presentation is just nonconforming of social expectations of her gender. Outside of that quirk, she has no issues with people seeing her as female and has no issues with her anatomy.
I am bigender. When I have top dysphoria, wearing clothing that hides my chest only does so much. It’s the fact I have breasts that makes me uncomfortable at those times. Being upset about people seeing me with boobs is then a side effect caused by the fact that my brain is telling me they shouldn’t be there, but the problem is not actually my presentation.
And, I mean, one issue tumblr overlooks is body dysmorphia, I’ve noticed.
You can be dysphoric about physical traits and still be cis. Muscle Dysmorphia is a thing, which is primarily in (cis) males where they view their body as too small/lean/etc and try to increase muscle mass. Think of it in a similar vein as anorexia.
Gender dysphoria is related to gender physical/sexual traits and often secondary sex characteristics. It’s more the fact characteristics exist when they shouldn’t, or are lacking when they should be there. The other primary thing is that when this are done to combat the dysphoria, like wearing a binder or particularly flattening sports bra for top dysphoria, are done, the symptoms go away.
Now, this is a generalized statement, as people can experience gender dysphoria differently. I’m of the school of thought that you need some form of dysphoria to be trans, because otherwise what is bringing about the idea that you’re not cis? It’s also fair to note that dysphoria is not constant and can be very mild for some people. Everyone experiences it differently.
One method is to read the perspectives of other people who are trans, how they figured that out, and see if it sounds familiar.
The question I’d ask first is: is there anything outside of your clothing/hair that makes you feel like you are not cis? If so, what is it? Does having/lacking breasts bother you beyond how it pertains to clothes? What about the stuff downstairs?
Note: Some people experience top or bottom dysphoria and do not experience the other until after the first type has been treated. Just like having issues with your chest size or presentation doesn’t mean your trans, lacking one and having the other doesn’t necessarily mean you’re not trans.
Gender is weird and ultimately it’s something you figure out with self-reflection.