"You look pretty today."
"Really? Ugh, I felt so ugly looking in the mirror this morning. My pants made my love handles plop out, and my hair was really flat, and I could not get my make-up to look right."
Have you ever had someone give you a compliment and then you just bash what they say with a variety of contradictions that leave them looking at you with a strained smile on their face?
I don't remember who told me, it was probably my mom, because she has always been the one to give me good tidbits of advice, but they said to accept compliments, not berate them by putting yourself down.
I don't know why it is sometimes hard to accept compliments - maybe because it's hard to see the good in ourselves, or maybe because we were raised not to brag. Some people might think that letting someone say something good about you means that you propping yourself up. However, that's not true. Accepting compliments means that you are accepting who you are, and the fact that others see something good in you.
Whenever someone compliments me, I try to say "thank you." It's always good to good to find a reason to compliment that person back too.
By the way, a woman once told my boss that it is impolite to say "No problem," when someone says thank you. She said you should always say "You're welcome." Now, her reasoning for this wasn't something I completely agreed with, but I do think it is good to get in the habit of saying "You're welcome."
So on your list of things to do, adding "Saying you're welcome," might not hurt.