Having tried a bunch of different ant patterns over the years, I finally found one I really like. It's easy to see, floats well and is exceptionally easy to tie. This one in particular, I'm going to tie on a size 16 Gateway dry fly hook.
The design of Gateway hooks allows a sliding loop knot to be secured to the eye. The knot can then be loosened to quickly change flies - a feature I found to be really nice when fishing terrestrials.
For thread I'm going to use UTC 70 Denier in black. Start your thread about 1/4 of the way down the hook shank and wind back to halfway between the point and the barb.
For the body of the fly, I'm going to use a Wapsi's Hi-Vis Foam Ant Body in the small size. Secure the foam to the hook shank so the Hi-Vis part starts at the eye. Bind it down with 4 or 5 tight wraps of tying thread. Wind your thread forward to the starting point and once again, bind the foam down with 4 or 5 good wraps. You can trim the head down a bit, the smaller white section will still be very visible.
Then trim the rear segment of foam off at an angle. Bring your tying thread back under the hook shank to just in front of the rear segment and take a couple of wraps.
On a hackle feather, with barbules 1 1/2 to 2 times the hook gap, pull down about 1/2 inch of fibers and snip them off close to the stem. This will give your thread some purchase when tying in the hackle. Place the hackle against the near side of the hook, below the foam body, and secure it with a couple of wraps. Then advance your thread forward, under the hook shank, to in front of the next segment. Take a few more wraps before moving your thread forward to behind the eye.
It's important with Gateway hooks to keep the thread back from the eye just a little bit so it doesn't block the gate of the hook.
Next, take 3 turns of hackle at the tie in point and then angle the hackle forward as you did with the thread and take 3 wraps at the forward tie down point. Then secure the hackle in front of the head and snip the remainder off.
You can then whip finish the fly, remembering to keep the thread back from the gate. Snip your tying thread free and then snip the hackle fibers off going across the top of the fly as well as the bottom of the fly.
Apply a liberal amount of head cement to the underside of the fly to make it more durable. You should end up with hackle fibers sticking out the sides like the legs of a real ant.
This pattern looks great on the water and seems to catch fish even when ants aren't around.