You can click a pic of yourself with your username and some message on a piece of paper. You may or may not reveal your entire face but show off something so that it looks legit and members can trust you. This is just a suggestion.
And yeah my friends (boys cause I am a male) also listen to the whole BTC thing and act as if they understand everything but at the end it always turns out that they didn't even listen to even 1/4th of the lecture.
Why would she need to do that? Would you do the same to prove you are a male and have friends? Plus, proving that she is a female won't make her more trustworthy.