Most of the dies are 2x2 or 3x3. You can cut the paper to fit those dies. I have actually cut some felt to just do one little piece of the die.
This is one of the dies I have. I just wanted to use the biggest fish. I cut the felt so it was just large enough to cover that fish. I put it thru the machine and that is all the felt I used. (I try to use 100% wool felt. It's expensive and I don't want to waste any.)