Provide users with an introductory overview to let them know how the procedure fits into their workflow. The overview tells users what information they need to know about the procedure, why they need to perform the procedure, how the procedure works, what benefits they gain from completing the procedure, what connections this task has with others in a process, and so on. The overview may contain prior conditions users need to meet and should provide some sense of goal or direction for the procedure. The overview may also contain scenarios or examples to help put the task in a broader workflow context.
Don't write sentences such as "Follow these steps to _____." Users already know to follow the steps, as they intuitively understand numbered lists and the presented structure. In addition, empower the user by putting him or her in charge of completing the task. For example, if you can, resist the temptation to write "_____ allows you to _____." Instead, write something along the lines of "Using _____, you can _____," which reinforces the user's ability to accomplish the given task.
Overviews have no set length. They are as long or as short as the task requires. More complex tasks require more detailed overviews. Just make sure the overview addresses the preliminary information users need to perform the task efficiently and effectively. At the same time, avoid over-writing the overview, because we don't want to intimidate our users.
Provide concluding information (if necessary).