I would try to do all the things reserved to women, in order to have them as a new experience. So
- changing bra
- trying intimate absorbent
- having experiences with male people as a "person of the other side"
- having sex as a woman with a man
I would also add activities like body shaving, but these are not limited to women (even if they are generally done more by them than by men), and I fact I shave my body even if am a male.
However activities you can clearly do only if you are a woman, yeah... I would try them in order to say "well, for 1 day I really tasted what does it mean being a woman".