No, don’t pick up after him but give him an incentive to clean it up. My son earns an allowance based on keeping his room clean – and a few other simple chores. He waits until last minute to clean the room and the job is far less than perfect but it’s exponentially better than it used to be! I do need to break the chore down for him into layers/steps: 1- Clean up all clothes. 2- Clear the floor. 3- Clean all surfaces. 4- Clean the bed. 5- Clean the closet. Usually 5 is on a separate day. He is most cooperative if I tell him one step at a a time. Good luck!