Well, here we are in the off-season, ready for another winter at the vise, making next season's flies. Here's a good floater pattern that just won't sink, no matter how wet you get it.
Hook: Mustad 94840 # 8-14
Underbody: Thin closed cell foam
Body: Polypropylene yarn
Overbody and tail: Deer hair
Hackle: Dry fly quality cape hackle
Thread: Monocord
This is just about the most floatable dry fly in my arsenal. Start with a standard dry fly hook and wrap a good solid foundation along the shank. At the bend of the hook, tie in the thin foam underbody, a strip cut narrow enough to wrap well, a strand of poly yarn and a small clump of deer hair at mid length, sitting atop the bend, tight enough to flair the tips. Run the thread forward to the eye and tie down with a loop knot. Wrap the foam forward to the eye and tie down. Wrap the poly yarn atop that and tie off at the same spot. Finally, form the loose deer hair into a neat overbody and tie down. Trim the excess and tie in the hackle. Wrap the hackle to form a thick collar and tie off with a wrap knot to form the head. Trim the excess and cement the head.
Everything in the construction of this fly (except the hook) is a floating material. When the hackle gets waterlogged, the poly still tends to float. So does the hollow deer hair. So does the foam. For this fly to sink, something has to pull it under. So you never need to false cast to shed moisture or stop and change to a dry fly when this one takes on water. You don't even need dry fly coating or crystals. This fly will float like a foam bug, yet it possesses all the lure of a fat profile dry fly like a Wulff or Horner's.
The color variations are many. Yellow, natural hair, and ginger hackle; Red, dark natural hair, and furnace hackle; Black, black hair, and black hackle; Green, green hair, and chartruese hackle; Beige, natural hair, and cream hackle. The list is a long one, and a wide selection can make the difference when the fish are being selective. This fly works for trout, bass, sunfish, and more, pretty much all year long, spring to fall, starting with the crane fly hatch.
Because it is bulky and relatively wind resistant, a heavier than normal line is needed. I personally wouldn't cast one of these on less than a six weight, preferably a seven. It is not a finesse fly, but at the same time, it is hard to slap one of these to the water surface. Do be careful not to overcast these and wind up with casting knots in your tippet. Step up a size, but don't try and force the cast.
There is something about the Humpy that has an amazing appeal to the fish and is hard to explain. All I know is that they work very well when other dry flies draw nothing.