I thought of one other thing that has been helpful to me - the notion of "hot spots". These are areas that clutter grows in uncontrollably if allowed to do so. Different people have different hot spots. I personally have way too many.
I picked one area to start with and vowed that I would keep that area clean and clutter free, checking on it everyday to make sure that one slip of paper didn't start multiplying and growing out of control. It's working for me.