I tie them with a longer and heavier wing, shorter and heavier tail, and sparser hackle (3-4 turns only) palmered through a contrasting and brighter thorax, Stimulator-style. I almost never use the caddis-specific colors. The original purpose of the fly was to come up with a faster to tie version of a Coachman Trude. That peacock version and a pink version get 90% of the sales at Parks, though the effectiveness of bulky caddis-style attractors has nosedived for me since about 2012. Since then the caddis-attractors work fine on rough water, but on pressured water including the Yellowstone they mostly only work in July and maybe the first week of August, the latter if the water is high. Otherwise, much sparser flies including ants and things like #16-18 Missing Links have generally worked a lot better. The year I first came up with the Coachman Clacka, it was basically all I had clients use from July into September. I think the reason is pressure. Yellowstone River fish are turning slowly but surely into Madison River fish in terms of their preferences...