This is really not the reaction she wanted. But, pressing on. "I'm not going to stand in here while you shower so pay attention. This is how you turn on the water..." She demonstrates it briefly, making sure they're both actually clear of the spray. "Left is hotter water, right is colder. When I go outside, you'll need to undress and scrub all of that gunk off of you. The shampoo is for your hair and the soap is for everywhere else. Just use a little shampoo, not the whole bottle. After you've scrubbed with the soap, rinse it all off with the water. Then dry off with this towel and change into the clean clothes. Does that make sense?"

She sincerely hopes it does, because really the last thing she wants is to need to monitor his bath.