I like to wear clothes that make me feel sexy most of the time BECAUSE they make me feel sexy primarily. The admiring looks from guys and cheeky comments/approaches are a bonus which fits into the whole picture.
I go braless underneath t-shirts and dresses most summers and my nipples get hard in the slightest breeze ;-) I've always been a dress//skirt over trousers kinda girl and the longest I have is knee length (and only one at that!).
As far as the supermarket goes, the naughtiest thing I've worn is a crotchless bodystocking under a very thin and short silky dress. The bodystocking had cut-out breasts and let me tell you my nips were hard from the naughtiness of it all. Also, like many bodystockings, the mesh pattern on the legs was very sexy/eyecatching with a sort of faux garter so it looked almost like regular stockings on the legs. Hubby was with me and he checked out guys checking me out that I didn't even notice and a few were a good bit younger than me
I also find faux leather leggings to draw a lot of attention and at yoga I wear scrunch bum leggings in the winter and always go near the front when their are guys. I love the feeling that they are enjoying my downward dog