It depends on what I'm tying. For a gurgler, I use 2mm foam and cut a strip of foam, tapered to a point. I lay it on the the length of the shank then wrap the foam down the length of the shank. I'll coat the shank with some super glue to make sure it doesn't move. Then fold the wider portion of the foam over the shank and then wrap it down behind the eye. Again I use super glue on the thread as I wrap it down. Once the glue sets, it's not moving. I use 2 mm foam for three other patterns. Two are poppers, one made from a foam circle, the other from a heart shaped piece of foam. For the foam circle, I lay down some thread at the tie in point. Coat the thread with a bit of super glue, pinch the bottom of the circle against the shank, then wrap the foam at the tie in point. Some super glue on the thread makes sure it doesn't move. The heart shape piece is tied in at the hook point. Liberal use of super glue. I also have an under body of foam, and I glue the sides against it. It leaves a jitterbug shaped mouth. The Crease fly really doesn't use any thread to tie it down. It's glued into shape. Let's see if the lay out works My sliders are pieces of foam, 3 mm to 6 mm thick. One is a strip of foam. Wrap it tight down behind the hook eye. The fold it along the hook shank, tying in the two pieces at the hook point. The other is an arrowhead shape piece. Tied in behind the eye, I coat the shank with super glue, bring the thread back, lay the body on the shank and then wrap back portion of the foam at the hook point.When working with foam you need to hold it in place with your fingers while you're wrapping. Use super glue on the threads and foam.