I'm not sure who coined this definition but it's ingenious. "Clutter is delayed decisions."
Look around a cluttered room and you will see a bunch of stuff that is not done. Either things just haven't been put away or haven't been sorted, haven't been taken somewhere, or have been there so long, they have been forgotten.
Pick up an item. What decision needs to be made about it? After you make the decision, does an action need to occur? If it takes less than 2 minutes, do it now. If not, and you don't have time to do it now, start a list. Continue the list with tasks that need to be done. Now take that list and "calendar out" when you will make time to do each task on the list. Listen to your calendar, do all the things, and voila...done. Try it!