I use Simple Green with warm water to clean, dry with rags, and lube with Finish Line teflon oil. If it's really dirty, clean it, dry it, lube it, and then do it all over again. You will see a lot of dirt come out of the chain when you lube it the first time, and less the second time. If you ride in the wet you are going to get a lot of grit in the drive train and you should be cleaning often if you want your chain and cassette to last a reasonably long time. After each significant rain ride I would at least rinse down the chain and gears to get most of the grit off it and relube even if you don't take the time to clean it.