My theme for the
April A to Z Challenge is Productivity for Creative People.
The gist of his book is about how to accomplish this. You can use electronic systems or paper notes and files, but the concept is the same. Do a giant brain dump. Then make sure you have a good system for following up on the deadlines, ideas, and tasks that you cleared. Allen says, "Your mind is for having ideas, not holding them." If you trust that your calendar and files, for example, will keep you from forgetting anything, your mind is less distracted and free to focus on the important creative stuff.