We use a 3 gallon stainless bucket with a handle, found it at lowes, and clipped a double sided clip (like the end of a leash, but with two clips) to it. One side to the handle, and one side to the inside of our 54" crate on a towel. Only the adults ever get crated in there, and they know not to overdrink so they won't wet the crate.
Spring - fall we used to keep the bucket outdoors only. They drank on potty breaks. But since we've put it in the crate, all the mess is 99% contained and they don't dribble on the floor anymore. So maybe this yr we'll let them keep one bucket inside.