Here, Matt Grobert, author, fly tying instructor and host of the blog "Caddis Chronicles" is going to demonstrate how he ties a soft hackle mayfly emerger. Although here he's tying a sulphur, by changing hook size and the colors of components, this pattern can be used to represent a large range of emerging mayflies.
Realistically, it can be tied in sizes 10 all the way down to 18. For this sulphur, Matt's using a TMC #100 dry fly hook in size 14.
For thread, he's using 6/0 olive Danville, and seldom uses anything else. For the rib of the fly, copper-colored UTC ultra wire in small works well. Begin tying the ultra wire in at about the hook point and take wraps back to the start of the bend. Wind your thread forward over the wire tag to create a uniform underbody.
Pull 5 or 6 fibers of pheasant tail from the stem. These have been dyed brown. Measure them on the hook shank so you will end up with a tail just a little longer than the hook gap. Wind your thread forward to in front of the pheasant tail and begin making nice uniform wraps with the fibers. Don't twist the fibers, rather, try to keep them in line and flat. Care must be taken at the rear of the abdomen so you don't release the fibers and have them unwind.
Secure them at the base of the tail with a single turn of wire then continue wrapping the wire in an open spiral up the body. When you reach the end of the fibers, tie the wire off and then helicopter until it breaks off clean.
You can then carefully snip the pheasant tail butts off close, being careful not to snip the tail fibers.
Pull your bobbin down to expose 4 or 5 inches of thread and then apply a light coating of sticky dubbing wax to the first 2 inches or so of thread.
For the thorax, Matt uses a rabbit hair, or better yet Australian Possum, blend. Here, for the sulphur, he's using rabbit - 3 parts bright yellow to 1 part bright orange. Carding, as Matt's doing here, roughly aligns the fibers. Once aligned, he'll touch dub thin sheets of fibers to the waxed tying thread. Without ever spinning the thread or the dubbing, begin taking wraps to form the thorax of the fly. Pull the fibers back occasionally to get them pointed rearward.
Once you reach the eye, gently pull the rabbit fur back and take a few wraps to form a smooth base for the soft hackle. Here Matt's using speckled hen back dyed golden olive, but regular speckled will work just fine. Pull the fuzzies off to expose the stem. Keep on removing fibers until you're left with ones that will reach back to just beyond the hook point. Get hold of the very tip and pull most of the fibers back. With the tip exposed, like so, snip it off but leave a small triangle that will aid in attachment. Secure the feather to the hook with a few tight wraps.
With your hackle pliers, get hold of the stem and then with your thumb and index finger, fold the fibers rearward. Take wraps pulling the fibers back as you go. Finally secure the stem to the shank. You can then snip the stem off close. Whip finish to form a nice small head and snip or cut your tying thread free.
It's absolutely fine if some of the rabbit fur pulls out. More will likely come loose during your first couple of casts. Don't be afraid to fish