For me it all depends on water clarity and weather. Keep in mind what weather does to fish and how it effects them. For example cloud cover, wind, cold and warm fronts, and the time of the day.
I either fish 3/8 or 1/2 ounce jigs. I have switched to only using dirty jigs pitching jigs and hp flipping jigs. I also rarely use rattles unless i'm working with very low light conditions or super muddy water.
Clear lakes - Mildley stained Lakes: 1/2 ounce jigs for a faster presentation so they can't get a close look at it on the drop. I like the green pumpkin, watermelon green, or pb & J jigs....sometimes a black/blue. But i like using trailers in either the same color or a similar color with some flake in it.
stained to muddy waters: I still start with a 1/2 oz jig if i can get away with it, but my colors only change a bit. I'll still use the pumpkin most of the time or a black/blue. but I try and make the jig have a bigger profile so they can see it better. bigger trailers and sometimes rattles is what it takes. I stick to solid colors for the most part though in these conditions.
But all that being said I'm starting to realize it's more about how you work your lure and how quitely and precise you can be with your presentation. If you are not catching fish after you are sure you are doing these things correctly, then maybe think about switching the color up. Another good rule of thumb is to try and match the bottom of the lake, crawdads and fish alike are chameleons. most of the time they will mimic their living conditions and have at least the same base color of the environment around them.