If a person has longer hair, no facial hair, is wearing a dress, has a higher voice, wider hips, and the appearance of breasts, I'd assume they are a woman.
BUT: if a person with all of those traits says they're a man, I'm going to nod, file it away for future reference, and -- most importantly -- move on with my day.
And likewise, if a person with none of those traits tells me they are a woman, again, I will nod, remember it, and move on.
If that's not what you're asking for, then it seems you're asking for a flowchart that determine's someone's gender. Gender being a social construct (as opposed to sex) there is no decisive flowchart other than: ask them; accept the answer. If you want something generally accurate, I stand behind what I said above.
"mindset" is actually a pretty reasonable descriptor I think (I'm not an expert though).
I think a lot of the confusion does come from people having a hard time separating "what does this person want me to call them" from "how do I treat this person". I think (again, I speak only for myself, and I'm not even trans) most trans people would be happy to be called their chosen pronouns and treated in a neutral way.
There is a lot of history backing up a more constrained interpretation of gender and interpersonal relationships, and the present situation is definitely outside many people's comfort zone.
If a person has longer hair, no facial hair, is wearing a dress, has a higher voice, wider hips, and the appearance of breasts, I'd assume they are a woman.
BUT: if a person with all of those traits says they're a man, I'm going to nod, file it away for future reference, and -- most importantly -- move on with my day.
And likewise, if a person with none of those traits tells me they are a woman, again, I will nod, remember it, and move on.
It's not hard.