You need a plan because there will be moments you will get triggerd to buy. If you don't have planned out how to handle these situations, you will be screwed.
I'm doing it because of the difficulty of it, not despite of it. The goal is to eliminate the urge to buy. Cold turkey drug rehab style.
When I looked into the cupboard at my mom's house to find some chocolate, I found a bottle of Moët & Chandon champagne. That bottle is standing there for years waiting to be opened.