The Balloon caddis is one of the most popular adult sedge imitations. Fish it singly on a long fine leader either static or twitched across the surface.
Take the thread down the hookshank to a point just opposite the barb, dub a small rope of seals fur onto the hook shank towards the eye.
Take a bunch of deerhair and even the ends using a "hair stacker".
Catch in the deer hair and secure, trim the waste ends.
Whip finish and trim the thread
Take a small piece of plastazote and catch in some thread at the eye colour to match. Secure the plastazote at the eye with the thread.