You might be tempted to fish emergers with a subtle twitch. It sometimes works during a caddis hatch or during an emergence of large mayflies like Green Drakes, but most times you are better off fishing an emerger like a dry fly—dead drift. Any movement you can impart to your fly is far more overt than the diminutive quivering of the naturals.
However, a slight amount of drag will sometimes trigger a strike, because it makes the fly move toward the surface. Trout will usually take the fly right at the beginning of the drag. Once the fly drags for more than a second or two trout will realize something isn’t right. This can be helpful when a fish is rising in a difficult spot like a slow back-eddy on the far side of the river, where avoiding drag is almost impossible.
Cut the last foot off your knotless leader and add 3 feet of Mirage tippet material of the proper size. Mirage fluorocarbon sinks the fly slightly, is much more transparent than nylon, and has been proven to be very effective when fishing emergers. Make extra sure you do not leave any Mirage tippet on the river, even if you have to climb a tree to retrieve a broken tippet. Mirage breaks down in ultraviolet light far slower than nylon an can present a problem to wildlife if you don’t use it responsibly.
It’s important to know exactly where your emerger is at all times. Some of them have wings of CDC, snowshoe hare, or poly yarn that stick above the surface. For the more flush-floating emergers, a tiny spot of Strike Putty two feet above your fly will help you track its progress.
Even if your fly is three inches below the surface, you’ll see an indication of a strike. It could be a swirl, but more often it will look like any other rise.
If you begin to see trout eating adult flies from the surface, you can switch to a standard dry—but the emerger should continue to work throughout the hatch.
Try fishing an emerger with no dry-fly dressing first. It will float for a number of casts and then it will sink just slightly under the surface, so you can see which works best. If you want your emerger to float, rub it in Shake & Flote, not liquid or paste dressings.