I'll put the fly in the archives, although it really doesn't look like much!
The flies are from 1/4" to 1/2" in diameter. Some are weighted with a short piece of lead lashed to the hook. One had a larger, heavy duty hook. Some aren't weighted at all. The yarn I'm using is Needloft Plastic Canvas Yarn. (Ames Dept. Store. 39 cents for a 10 yard skein. Probably even cheaper now because they're going out of business.) Let's see: I use 3 - 4" per fly, so one skein will make over 100 flies!
The flies all sink quite slowly and sometimes even float right after casting if I make a couple false casts first. A quick tug will pull the fly under and the fluoro leader helps it sink. The heavier ones will pull the end of the fly line under and sink to the bottom if there's not much current or wind, but the light ones drift above the bottom if the water is more than a couple feet deep.
BTW, I went back today to look for the big boys but I still didn't find them. The wind didn't allow for much "looking" but I did manage to get a bunch from 2 - 6 lbs. A few were caught blind casting on the flats where I knew there were fish. Most were caught by "semi" blind casting, where I would cast towards fish or moving shadows, although I couldn't actually see them hit the fly. The rest were sight fished. It still amazes me that they will actually turn and/or change depth to eat or inspect the fly. I'll have to try these flies in some other places where the carp are bigger but not as plentiful. Maybe the little ones are stupid, or perhaps they just have different feeding habits.