DS2 is now pooing in the loo most of the time. Most of the time we wait upstairs until he's done it, then wipe for him, as you would do for a younger child. If for any reason we aren't nearby he uses his hand to wipe, then wipes the hand on any and every available surface. He doesn't yet have the coordination or motor sequencing skills to use loo paper or wipes. He never calls us, so can't do the 'wipe my bottom' call of an NT 3 year old.
How do I teach him this skill? What do others in this situation do?