What color(s) work best in clear water?  Stained?  Muddy?

Also, does this change when you switch between soft plastics, hard baits, and spinnerbaits?

Thanks for any help.

Clearwater, you generally stay with the green and more natural colors, murky and dark you can use bright colored lures. Although i would be more worried about your presentation as thats what triggers the strike.

There are general guidelines, as stated in the prior post. But bass don't know those guidelines, they take all colors in all water clarities. Color just isn't at the top of my list of factors to consider, but it's much more important to some other people. You need to do what feels right and gives you confidence.