I DESPISE shopping for clothes. My best bet is to find a friendly female NT (emphasis on "friendly") and let her guide me. I do put my foot down, though, and refuse to wear anything that isn't "me."
I am a t-shirt and jeans/sweats kind of person, but sometime I have to dress up (something NTs call "business casual," and if THAT'S casual, I wonder how fancy the next level up is???). I learned that if you buy 4 pairs of pants and 4 shirts and they all go with each other, you can make sixteen outfits! I stick with three basic colors: black, gray, and red. They are acceptable clothes for females, but not particularly "feminine."
For normal everyday wear, though, it's t-shirt, sweats/jeans, and a baseball cap.