Once you unlock Elizabeth's fashion review, she's REAL picky and annoying. She insults pretty much everything you try on, but I discover what she wants to see. In the entertainment area, there's a house by the casino that has a bunch of clothes on display, and those are the clothes to wear!! To help you remember what they are, try taking a picture by them, it helped me. I don't know if it matters what hairdo/headgear you wear, but I usually keep it simple. I've actually got her to like my outfits a few times, and she's given me a rare item, like you can buy from Tracy and the casino. It also matters what you wear in what area, but you'll have to experiment!
I hope this helps!!! ~*~ :) brandflakes :) ~*~