Remember all the work Wally and the Beav put in to fake taking a bath? Wet the washcloth. Dampen the towel. Throw a little turtle dirt in as the tub drains to leave a ring. LOL.
I tried that, too. Finally got busted when asked to show my hands, which were strangely unwrinkled for having soaked in bathwater. Doh! My next trick was to soak my hands in the sink. I think I finally gave it all up as being too much trouble.