Dressing sexier is the obvious one. Retro/’50s fashion is more-or-less socially acceptable these days, so it wouldn’t be too weird if you started dressing that way (and who cares if people think you’re weird, anyway, as long as you feel good?). If you don’t want to go the whole hog, you could incorporate some subtly sexy touches, like seamed stockings, red lipstick, etc. And a black pencil skirt is a great investment for practically any woman, IMO. (Mine is from Ureshii and I love it!)
Another trick I sometimes use: when you want to feel sexy in the moment, imagine a hypothetical person who you find very attractive and who finds you attractive too (e.g. I might picture Raul Esparza in a universe in which he was an admirer of mine) and then pretend that that person is watching you. It sounds simple, but it’s actually a really useful exercise (at least for me) in re-focusing your behavior and attitude, allowing you to feel and act more sexy/charming/whatever.