When you know you have to get rid of a large amount of stuff, but you can't quite make yourself get rid of the entire amount, choose a percentage that you know has to be gone. That gives you some leeway on what you can keep. It also forces you to go through the entire batch and figure out exactly what that percentage is.
Say you have 100 magazines that are taking up half a closet. You are allowed to keep 40 of them, but 60 have to go. Go through the entire 100 magazines and choose your 40 favorites. You are not completely out of your favorite magazines, but you have a more manageable load. Before you know it, you will eventually want to lose a percentage of the 40 you have decided to keep.
