Depends on the character, to be honest. My wizard, I've gone out of my way to avoid describing her to the rest of the group because she's very bland, so nobody really can agree on what she looks like. I wouldn't describe her changing clothes, or even really doing anything that called attention to her.
My druid builds her entire wardrobe out of random trash that she finds, and it's never quite the same from day to day. For her, I'd absolutely describe exactly what she's dressed up in.