For anyone who wants the short version, here it is:
 
1.     Break tasks down. Goblin.tools can help with this.
2.     Set a 15-minute timer and clean one small area.
3.     Use colorful sticky notes to remind yourself of tasks.
4.     Do the most critical task first.
5.     Progress over perfection.
6.     Another person’s presence can help with motivation and focus.
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Garage/Shed

The winter grime and all sorts of items find their way into the garage with no site out. Open the garage door, turn on some music, and get started decluttering. The more things you have on the ground, the harder it is to use the space you have. Try some wall organization, linked here. Cabinets are great in a garage, too; make sure they are easy to open up and see what you have. Don't let the cabinets turn into a place to shove things. Out of sight is not out of mind! 

If...