I've written a lot about this here, so I don't want to just repeat what I've said on other posts. LOP, what you said about dressing for different roles resonated a lot for me, except I'm not sure that all the parts of my personality and roles are related to femininity.
There's also a division within myself, though, in terms of how I view gender intellectually and how I actually treat gender in my own life. Intellectually, I view gender as constructed, and even sex as largely constructed, with few essential or "natural" components. (There are exceptions, obviously, which is why I said largely.) Dress, then, is one way that we construct our gendered identity and, in turn, a way in which we are constructed as "female" or "male."
All that said, when it comes to the way that I carry myself, the way that I dress, and the way that I generally act, I think most people would say that it's very feminine. I've struggled with this in a variety of ways because in some ways I know that it undermines my authority in professional settings, especially since I'm also pretty petite. I also think that my appearance allows me to "get away" with some more radical views and still be accepted within pretty mainstream groups because I don't "look" like a radical feminist and therefore I don't seem threatening in that way. I feel, though, like I'm selling out in some ways - like I'm disguising myself for my own convenience, or for other people's benefit, or something inauthentic. Yet, I really really like heels, and sometimes I even like clothing that is sexy, as identified earlier in the thread - pencil skirts, form fitting tops, etc. (I don't think I ever dress in a way that is vulgar, though.) I'm not reconciled to the fact that I like these things, though - I'm always trying to resist it and examine my own reasons for being drawn to those silhouettes.
Finally, I'm starting to realize that I would like to incorporate a little more "toughness" into my look, which isn't exactly masculine but not feminine either (nor is it exactly androgynous). This is really new territory for me, though, and I think it's partly related to feeling a bit vulnerable in other areas of my life and wanting to compensate by looking less vulnerable at least.