This is REALLY good advice! Show him how to cast somewhere that he doesn't have to worry about water at all. In the street is a pretty good place. You can have him learn to get the line where it needs to be so he is prepared ahead of time. Trying to learn to cast, mend, drift etc is really a lot for one day...Learning to cast and catching fish are mutually exclusive. Cast in a yard Saturday and then go to Spinney and fish indicators Sunday. Moving water adds complexity. Good luck.