There have been a few threads in the past where people have mentioned seeing a crossdresser in public and they didn't know whether to approach them or not. Usually, they opted to remain quiet, perhaps in fear of possibly outing themselves, or, maybe, not wanting to embarrass the person.
If someone sees you out and about, how would you like to be approached, if at all? And if you don't, is it because you would be embarrassed or what?
Personally, knowing full well that I don't pass as well as I wish I did, I wouldn't mind someone coming up to me and saying "hello." Who knows -- maybe it'll be the start of a friendship.