7. Don't Eat The Last Slice Of Pizza
I know this is like the willpower test of a lifetime, but for the love of god leave the last slice for your roommate in the fridge every now and then.

There is a loophole though: You don't have to do this every time – we're not saints here. Getting coal is like a Pass/Fail class – you just have to squeeze through with the bare minimum.

Found on Pinterest here, from How Sweet It Is.