Sitting down on the toilet to urinate helps a great deal. New habits are hard to get started, hope he is agreeable. Some men believe that masculinity is about standing up to urinate, so he may be reluctant.
Sitting down to urinate is the practical answer. I agree that some men will fight that, but unless cognition is at a level where he can't understand what's happening, hopefully he'll cooperate. I would suggest, however, that he see a specialist about this issue. It's possible that something can be done to help him. Take care, Carol
Take care,
Carol