Jack Gartside's gurgler is absolutely one of my favorite patterns for both saltwater and fresh. There are tons of variations but we're going to tie one here that resembles the original. The key to the gurgler is it's action. With slow pulls, it moves along the water's surface not unlike a slider, pushing water and creating a good looking V shaped wake behind it. Stripped with a little more authority, a gurgler acts more like a popper, creating splash and bubbles.
For saltwater, I like to tie gurglers on a Mustad 34011 hook, it's extra length puts a bit of distance between the fly's soft foam body and toothy critters. The extra length also makes it imperative that your vise has a really good set of jaws to hold the hook securely.
For thread I'm going to use UTC 140 Denier in red. Start your thread a little more than halfway down the hook shank from the eye and snip off the tag. I use 52 lb mono to create a loop at the back of the fly which helps to support the tail and keep it from fouling. I'll double the mono back to make the loop very secure as I will often use it to create a tandem fly rig.
Snip a small bunch of long white bucktail from the hide. Measure it to create a tail that's one full hook length long. Cut off the butts at an angle and then secure the bundle to the top of the hook shank.
Snip 2 or 3 strands of silver crystal flash from a hank and double it around the barrel of your bobbin, then move it up and secure it to the top of the hook shank. Trim the crystal flash off, about a 1/4 of an inch longer than the tail. Now repeat the same process with 2 or 3 strands of flashabou. Here I'm using a medium width.
Finally, snip a small bunch of blue deer hair from the hide and measure it to length. Cut the butts off at an angle and then secure it to the top of the hook shank with nice tight wraps.
A small paper cutter works really well for creating uniform strips of foam, in this case, 1/2 inch wide. The foam sheets from craft or office supply stores work just fine. You can get a bunch of colors for just a few bucks. Taper one end of a strip about a hook shank's length. This will make it a good bit easier to secure to the shank of the hook.
Place a drop or two of zap-a-gap on a sticky pad and then use your bodkin to pick up a small amount. Apply this only to the front half of the wraps, not at the tail where the foam will be folded over. Starting just ahead of the wraps, secure the foam to the shank, checking for length as you go. Stop wrapping right at the base of the tail, then wrap forward to really secure the foam.
For gurgler bodies, I like crystal chenille. Putting a small hole in the bag makes access easier and saves material. Tie the chenille in securely and advance your thread up the hook shank, then make 2 or 3 good half hitches. If you have a rotary vise, place the bobbin in the cradle and rotate the vise to advance the chenille up the hook. Secure the chenille with nice tight wraps but leave some space behind the eye.
Fold the foam strip over and take 4 or 5 nice tight wraps of tying thread. Then fold the front flap back and take more wraps to prop it up. Snip the foam off leaving about 1/2 inch lip, which you'll cut to final form later. From the cut-off, snip a 1/4 inch segment. Center the segment on top of the fly and secure it with a few increasingly tight wraps. Then return your thread to underneath the lip of the fly, take a few more wraps and finally whip finish a time or two. You can then snip your tying thread free.
Make another small puddle of zap-a-gap on the sticky pad and use your bodkin to coat the bottom front of the support foam. Push the lip up to bond it to the support. This little support really helps to keep the lip of the fly at the correct orientation. Add another drop to coat the rear part of the support and affix it to the back of the fly.
With that done, use scissors to shape the lip. I like circular but the shape is really up to you. Apply head cement, in this case Hard As Nails, to all the exposed thread wraps and the fly is done. As you can see, the lip is well supported and will be more so once the cement dries.
Look at this particular tie as a jumping off point. As you can imagine, there are nearly limitless variations of this pattern.