In your humble opinion, how do you tell the difference between men and women?

Ok, so, if the purpose of the thread is to find out how to identify whether cisgendered people are men or women, it stands to reason that there must be a way to distinguish between cis and trans people (so you know who is exempt from your need to catergorize them by gender).* Right?

So tell me, how do you identify, on sight, who is cisgendered and who is not? Think really hard here, because I’m pretty sure there is no way to answer this question that doesn’t reveal all sorts of bullshit stereotypes.
*Which is important, why, exactly? So, you don’t know a person well enough to know which gender they are, or how they identify. If you don’t know the person well enough to have this information, *what the fuck difference does it make to you * whether they are man or women or both or neither?