A character is never a whole person, but just those parts of him that fit the story or the piece of writing. So the act of selection is the writer's first step in delineating character. From what does he select? From a whole mass of what Bernard DeVoto used to call, somewhat clinically, "placental material." He must know an enormous amount more about each of his characters than he will ever use directly--childhood, family background, religion, schooling, health, wealth, sexuality, reading, tastes, hobbies--an endless questionnaire for the writer to fill out. For example, the writer knows that people speak, and therefore his characters will describe themselves indirectly when they talk. Clothing is a means of characterization. In short, each character has a style of his own in everything he does. These need not all be listed, but the writer should have a sure grasp of them. If he has, his characters will, within the book, read like people.