Staging is where you break the overall task down into intermediate stages. So you wouldn’t jump straight in and ask students to write a summary of something they’d just read, for instance. Instead, you’d walk them through the process of getting to grips with the vocabulary maybe, picking out the key points and then paraphrasing them to eventually produce a summary. The number of stages you choose will depend on the complexity of the text relative to the students’ language level and their experience of coping with the task type; is it the start of a new course or have you already gone through a number of similar activities together in class?