If You're Sleepy, Then Go To Bed!

If You are tired, then don't organize. If you are organizing and you're getting tired, then stop organizing. 
It's always good to organize when you are wide awake and motivated! So if you are worn out from outside activities, then don't try to clean out a space. If you have been organizing a room for the last six hours and you are genuinely exhausted, then end the session. If you continue, you can seriously hurt yourself (or others) and you won't do a good job. You may miss something important. Stop while you are wanting to continue.