I got a tool set from Making Memories that called a "Universal Eyelet Setter." Never asked how to use it (mistake number one).
Just now, I went to the Impress Rubber Stamps site and learned that I have been trying to use the FINISHER instead of the SETTER. The little pointy thing that I never used is the SETTER. It makes a much smoother, rounder opening on the back. The little bumpy groovy things are the FINISHERS.
I just put an eyelet into a folded scrap of cardstock and it works 10 times better this way.
Thank you Melissa!