Whether home-made or store bought, you’ll want to be sure to store your ice cream in the coldest environment you can find. That means the freezer, obviously, but more so at the back of the bottom-most shelf. Why is this important? Because as ice cream is warmed and chilled with each subsequent removal from the refrigerator, larger and larger ice crystals form. That over time will make your ice cream grainier, and when those ice crystals evaporate (yes, evaporation happens in the freezer, just much more slowly than in the fridge), your ice cream will get harder. Another nasty side effect of a prolonged stay in the freezer is that the fat in your ice cream will start to absorb odors and flavors from other foods (yes, just like in the fridge, it can get mighty smelly in there). All the more reason to just eat the ice cream and be done with it. Really, it’s the only proper thing to do.