As CDers we tend to come across as devious and boundary pushers, so one option would be to move slowly and if you see her in something nice - reply by asking her if you could borrow it (leggings, t-shirt tops, mascara, eventually blouse or skirt) and work up to fully dressed without a wig. She will probably ask you at some stage if your interested in cross dressing so a YES, followed with "are you gay?"
Or option 2, just say how lovely she looks and you wish you had the opportunity to be dressed to look so beautiful.
Or option 3, just tell her you like to dress in womens clothes (and duck, because she will feel the years of your hidden secret)
Or option 4, "accidently" discover a web page like mine or the many others, and ask her opinion on the subject
