The widely accepted theory is black or black/purple at night. On a bright full moon w/ no clouds, black/yellow.
But when you read Kayak1's posts, he kills em on yellow at night.
I've done well on silver at night and also caught on white at night.
Personally I think the profile and action are what catches for the most part.
However, at times certain colors kill em and others go untouched.
You have to figure out what plug style and color you have confidence in. And the only way to do that is put in a lot of time on the water.
I have a big crate in my truck full of plugs of all styles and colors. I just told Jason the other day I'm gonna trash everything but the SP Minnows. That lure has caught 75% of my fish this year. It has great action and I have confidence when I'm fishing it.