Actually we dunked our cat in a bucket of water in 1995 when the fleas were very bad, we chose this over putting chemicals on her. We put her in a skinny enough bucket which helped in the restraining, and ensured the water was warm. We didn't come out too badly actually but there were two of us. The fleas thankfully all abandoned cat via her nose, so we did have to put her under (briefly), it did a great job on the fleas. Anyway if you have to, skinny bucket is probably better as it limits the paw movements, we towel dried her and gave her a tin of tuna after, and we did have to do it one more time and she wasn't too bad.