Hemingway has a great description of his writing rituals in A Moveable Feast when, as a young writer with enormous self-confidence, he used to go out and write in one of a selection of cafes in Paris near where he and his new wife were living; he had to have a rabbit's foot in his pocket.
Karen Pryor has a chapter about rituals, or what behaviouralists call 'superstitious behaviour' in her book Don't Shoot the Dog. "I have seen one baseball pitcher who goes through a nine-step chain of behaviour every time he gets ready to pitch the ball," she writes – "touch cap, touch ball to glove, push cap forward, wipe ear, push cap back, scuff foot, and so on. In a tight moment he may go through all nine steps twice, never varying the order. The sequence goes by quite fast—announcers never comment on it—and yet it is a very elaborate piece of superstitious behaviour."
Do musicians have similar rituals?