This is just like doing a wingcase on the Hare's Ear and Pheasant Tail

Whip finish then start with brown or black thread.



Grasp wingcase with right hand.
Pull forward between any hackle or legs depending on the fly. Onsome flies, you may want to trim hackle on top as with a Montanastone, march brown, if you have palmered a hackle across thorax.
Hold wingcase with good tension as you make a loose wrap of thread.
Notice how wingcase is still straight forward. You may want to angle it toward you a little so that when we tighten thread, thread torque doesn't pull case material to far side of shank.


Tighten thread. Let the thread pressure bring the wingcase material down to the hook shank, this keeps material in a neat bundle on top of shank. Maintain thread tension and add 4 or 5 more wraps.
Cut excess wingcase close to thread wraps.