Oh, my - I can't believe I didn't figure this out sooner!
I am not good at cutting anything that's not a straight line. Curves are too complicated - not to mention anything with an actual shape. And then I read that the best way to cut curves is not to turn the scissors, but to turn the paper.
You know what? I tried it - and it works! And I learned this just in time - I have 2 dozen cupcake wrappers to cut for Miss M's birthday party this weekend!