I always used to point out why they shouldn't compliment me. I used to get very defensive and point out that their hair / whatever is nicer than mine etc. I think it used to be a way of pointing out that I didn't think I was worth noticing and re-directing them to noticing something else, but also used to worry that they were being sarcastic (I really didn't believe they were geniuine).
I then realised that this wasn't helping my self-esteem (which, as you may have guessed, was a bit of a problem) and that if I had put time and effort into something that them recognising this was a genuine attempt at them letting me know that they'd noticed and that them noticing and taking the time to tell me meant that they genuinly cared a little bit about me and my happiness.
Now, if someone compliments me, I take the time to appreciate that they wanted to make my day a little bit better and that they care. I can genuinly smile at that thought and say thank you. It doesn't have to be at the compliment, but at the fact they took the time to say something.
Part of my problem accepting compliments was that I didn't think I deserved them. I didn't think I was worthy of other people's attention. But then I came to realise that everyone deserves to feel good and that includes me and you! Therefore, take the compliment with a smile in your heart and go out with your new hair-do and make-up, look good, feel good and let the world know you appreciate them noticing

*hugs*