Well, on occasion I will ask my daughter if she thinks "x" or "y" wouldn't go better w whatever she is wearing. If she didn't put a lot of though into her ensemble, she will often agree and make a change. If she is confident in her selections, she will just say, "Thanks for your opinion, but I like it". That will put ya back a few. :) So, you could try to politely, but with conviction, let your mom know you are sure of your choices - so sure that you are impervious to her disapproval.