Choosing the one thing
If you're going to work on one thing at a time, you have to choose which. For many people this is where the method stalls. There are eleven things, all of them seem urgent, and picking one feels like neglecting ten. Juggling lets you avoid the choice, since you can tell yourself you're attending to everything. This chapter is my own set of suggestions.
Write the pile down. Get every open task out of your head and onto one sheet. Include the half-written email and the form, and include "Ring Dave back". It usually comes to between eight and twenty items. Seeing them listed is already a relief. Chapter 11 explained why, since an item on a trusted list stops knocking.
Ask two questions of each. What happens if this isn't done today? And who is waiting for it? Most items turn out to have an honest answer of "nothing much" and "nobody yet". Two or three have real answers.
Pick by consequence. The item that makes the most noise isn't always the important one. A colleague's third reminder is loud, and Thursday's report is silent until Thursday. For the first stretch of the day, choose the item where not doing it costs most. That's very often the one that needs sustained thought, which is also the one that suffers most from being juggled.
Do the big thing first. Your first ninety minutes are usually your best, and the day hasn't yet filled up with other people's requests. If the report gets those ninety minutes before you open your inbox, it moves. If the inbox gets them, the report gets what's left over, in fragments.
Limit what's open. Decide on a number of tasks you'll allow to be in progress at once. I'd suggest three. When three things are open, you don't start a fourth until one is finished or deliberately dropped. People who manage workflow in factories and software teams use limits like this. They found the same thing as chapter 11's arithmetic, which is that fewer items in progress means each one gets through faster.
Shrink what can be shrunk. Some pile items are two-minute jobs that have been open for a week. Ringing Dave is probably one of them. Give those a single batch of their own. Half an hour of clearing small things, done as one deliberate stretch, removes a lot of background noise.
Drop what can be dropped. Some items have been in the pile so long that they're never going to be done. Cross them off on purpose, and tell whoever needs telling. If you decide to drop a task, it's finished, and you're no longer carrying it.
Write down the one thing. When you've chosen, put it on a piece of paper in front of you. "Report, section two, to the end of the costs paragraph." It sounds childish, but it works. When you look up from a message twenty minutes later and wonder what you were doing, the paper tells you.
You might object that choosing takes time you don't have. It takes five minutes at the start of the day. I think those are the most valuable five minutes you'll spend, because everything else in the method depends on them.