I'd tell you...if I ever noticed such things. I think the tragic fact is that men notice what you're wearing or how you're groomed much less that you think they do. I mean yes, we'll notice that your hair is not full of lice, or if you've trimmed your pubes into the shape of Ronald Reagan's face, but by and large, we're there to look at the parts of your body you've chosen to reveal and then enjoy your company (in that order).
Don't get me wrong: if my wife puts together a stunning ensemble, I appreciate it, and I'm not too stupid to realize to pay her a compliment. But I also think she's incredibly hot in a girlie tee and a pair of PJ bottoms. Always have, always will.
The sexiest thing is to carry yourself with confidence, kindness and grace. Wear the clothes that you feel comfortable in, and that will come a lot more easily. Dress to make yourself feel good. That makes you happy, and when you're happy you glow. We like that. That's really hot.
If you don't stink and you're not vapid, we're usually just going to be pleased that you deigned to spend time with us. And even if we aren't, slapping on some strappy heels isn't going to make the difference. It may get us to sleep with you, but that was pretty much a lock from the get-go.
I know that even though I'm just reading this now it's actually from August. But did Michael not notice that this question came from a guy, not a female? Clearly he wants to know if he needs to shave and wear clean underwear for a "hanging out" meeting, and he wants to know how much more effort he needs to make for a formal date (should he shower?). If it's not too late, it would be interesting to know what other guys think is the appropriate level of grooming for different types of encounters.