Clear a little space by returning things. Things that do not belong to you, or things that need to go back to the store.
Did you borrow something from family or friends? Or have you been storing something for them? Did they leave a casserole dish at the barbeque?
Are there library books or videos that are ready to go back? (Hint: You do not have to wait for the due date.)
Have you purchased something that for any reason is not suitable?
Set aside some time in the next few days, load up the car, and deliver all that stuff. Your conscience and your house will be lighter.