We made up a game to help our daughter, age 3, get ino the habit of washing her hands after using the bathroom.  Each time she washed up, Ellie would secretly choose from two different scented soaps we kept by the sink.  When she was finished, we would try to guess which one she used by smelling her hands.  9She stumped us a few times by using both!).  Having a choice about what soap she used made Ellie feel like she had a little control, and it turned a shore she didn't like into a fun game.