Hello Erin.
If I were you, I would go to my first appointment dressed in a way to be the most confident and calm as possible, since a first appointment is always making everyone nervous. Personnally, I went to my first appointment in short shorts and a tank top ,which were very feminine i would say, but the decisions they will take for you will not principally depend on your physical appearance. I would go for what I believe to be the most appropriate for me, to make sure that everything will happen as it is really supposed to be happening . The key is to be honest to yourself.
Good luck !
Eve. -xoxo-