You use a comb to remove the hairs, then wash the bristles and handle with soapy water. If it's a plastic or hard rubber brush, you can soak it in warm water with some Dawn dish soap. If there's styling product buildup on the bristles, a wet cleaning toothbrush with some soapy water works well. I'd try to avoid getting rubber pads and wooden handles super wet as much as possible, and don't immerse them, but they can be wiped.