I've never done it before but I think they use a toothpick to roll on the edges to make the ruffles. I could be wrong but that is what I would try.
This might help, directions and cutters:
I'd say they'd be garratt frills... can get a special cutter for it.
I have to try this especially since I have to of the garratt frill cutters.
I agree with Feefs, it's the garratt frill cutter and there is a special tool you can purchase to roll the edges. It's like a ball tool but instead of a ball on the end it's cone shaped. I'll see if I can find a link and post it.
Thank you for all your help. Have a Merry Christmas!