This summer I was in a fly shop in Idaho, and the owner was tying these as fast as he could put them out for his guides on the upper Columbia river, and he was just using Light Cahill thread and a couple of turns of peacock for a thorax. One thing that makes a nice appearance is to strip off the fibers on one side of the hackle, then wrap that side next to the hook, it "sparsens" the appearance. This is only practical for the larger feathers, though, as the stems get too flimsy to do it on smaller feathers.