keep two to-do lists, one “open” and one “closed.” The open list is for everything that’s on your plate and will doubtless be nightmarishly long. Fortunately, it’s not your job to tackle it: instead, feed tasks from the open list to the closed one—that is, a list with a fixed number of entries, ten at most. The rule is that you can’t add a new task until one’s completed. (You may also require a third list, for tasks that are “on hold” until someone else gets back to you.)