Which British actor said to an eminent American TV and Movie actor 'You're doing it the wrong way round, my boy. You're a star and you don't know how to act'?
I wonder if this is a reference to Sir Laurence Olivier's comments to Dustin Hoffman when they were filming 'Marathon Man'. Hoffman tried living as a down-and-out in order to get into his part and Olivier suggested that he should "Try acting", which was much easier.
Actually, Hoffman's part was not as a down-and-out. He did, however, have to play a scene in which he was supposed to be exhausted. He made it realistic by running until he really was tired out. Olivier is claimed to have suggested: "Try acting, dear boy!"