At auditions, how you look matters. You want to show the client and/or director how easy it is to see you in whatever light.
I’m asked to wear a wide variety of clothes to suit different roles I’m supposed to play. A businesswoman requires a matched business suit (not separates), a mom a sweater set or simple blouse. Ffor business casual, khakis and a blouse or sweater set are de rigeur. Nice casual means good jeans and a sweater or blouse. Solids are usually preferred over bold prints. You need to know not only what colors look good on you and on camera, but at the various casting agencies. One has a very blue background, so if you wear a similar shade you could blend right in and look like a floating head.