As soon as your cakes cool, wrap in plastic wrap, first do one side then the other, then place your cakes on same sized cake boards.
You can stack a few cakes, then wrap the whole thing in more plastic wrap.
If I'm going for long term storage, I then place in large dark plastic bags that I squeeze the air out, then tie.
I never keep my cakes frozen for more than 1 week or less so I actually skip the Dark plastic bag step. But I have had cake that has been frozen in this method from a chest freezer that had been stored for over 9 months!!!!!:eek: