[header] How to wash a dog afraid of water [title] Fill a tub with a shallow layer of lukewarm water. [step] Bring the dog into the room and praise him in a gentle, encouraging tone. Place him at the edge of the tub, stroke him to help him calm down, and slowly introduce him to the water. 
It's ideal if he steps in on his own, but you may need to place him in the tub yourself. Give him a treat if he stops trying to leave.