When I come home from the grocery store with meat I package it as soon as I get home. If it is ground meat I portion it into 1oz meatballs (using my scale) for recipe usage and portion control that way I know that I am getting the right amount and am less likely to ever eat, it's also easier to defrost. My chicken I portion to about 5 oz per package. I have noticed that I don't need to eat as much meat as I thought I did.
Before doing this I would sit down to eat and have an 8-12 oz piece of chicken and not even think twice, but now I know that I was eating enough meat in one seating that I need for a day and a half. That is a real eye opener. Have finally seen the scale begin to move in the right direction again.