This is an old traditional fly, predating me by a long time. But I'm including it because it is spring, and the crane flies are stirring up a lot of activity on the water. It's a very simple fly, just hook and long hackle, but it can be very effective on many species of fish if fished properly.
Hook: Mustad 9523 spider hook #12
Hackle: Spider hackle*
Thread: 6/0 prewaxed
"What is spider hackle?" you ask. It's a rather rare blend of big and dry fly quality. It's usually a saddle hackle, on the order of spade saddle, but it it is dry fly quality, no webbing, stiff, resilient, water resistive. If you look around in the tying catalogs, you'll run across some for sale. The better the quality, the more effective the fly.
The hooks are a special hook as well. Spider hooks are the dry fly version of "egg" hooks. But don't try to use egg hooks, for these are true dry fly hooks. Size #12 is very typical, and it may be the only size that you can find. But a #12 does quite well for just about every application.
Tying is quite simple. Place the hook in the vice, apply a solid foundation. Tie in the hackle, wrap a few times (not too many, as the fly becomes really wind resistant in a hurry), and finish with a wrap knot and cement. Store loosely in a large compartment so as not to crimp the over-sized hacle.
This fly weighs next to nothing, so the lighter the casting line, the better. However, if there is too much hackle, it's not going to go down too far. Sparce is better. The trick here is to keep casting the fly to the same spot, not letting it sit very long at all. Tickling the water with the hackle, avoiding the dipping of the hook, is what makes this fly so amazingly effective.
In the early season, the crane flies are out over the water, bouncing all over the place, shy to stay still for too long while trying to lay eggs. So they bouncing up and down over the water, and the games between the flies and the fish get the fish set to hair trigger responses. So touch and go to the same spot is the key to success. Repeating the cast the same way is a must. The fish must have enough tempting to decide to make the take, and it has to sit there long enough for the fish to respond and be able to catch it. But it can't sit there any longer, or the hook will touch the water and spoil the illusion. The fish, if properly teased, will be waiting for the drop and will time it's strike to coincide with touchdown on the water.
This is very much a tactic fly, used the same way on moving water and still. Touch the water, pick it up and put it right back in the same area, no more than a few inches away, time and again, until the fish can't stand it. This makes for a great sight fishing technique or for fishing to obvious cover. It's not the sort of technique for covering ground, as it needs to be too meticulous. High percentage locations are a must target. If necessary, use a streamer or other fly to evoke a response, then come back to the spot with the spider and evoke the fish. The strike will not be a dimple. It will definitely be a splash and a half.