I used to have some tutorials up on another board (was scrubbed accidentally during a picture sweep). Thought I had downloaded here, but looks like I didn't. I think I may have a link to another site that had some up. Did you have a specific steelhead fly in mind? Some use marabou simply as a wing, some use is as a hackle/collar. Something like an Alaskabou or???
Depending upon the size of the fly that you're tying, you may need 6 or more marabou feathers. Of those 6 feathers, I like to use two or three different colors. As an example, I might use 2 yellow, 2 orange, and 2 purple or something to that affect. I also routinely use different shades of blue and then finish with black. Guinea collars in various colors and a bit of flash finish the fly.
All you need to do is to palmer the marabou around the hook and make sure that the feather wraps are as close together as possible. As you palmer the feather, make sure that each of the fibers are perpendicular to the hook. If you use as many marabou feathers as it takes to complete the fly, you'll be rewarded with a fly that will not collapse once it's wet and under pressure from the current. I do not care to weight marabou flies. This process is easy but takes a fair amount of time, I'd say 7-8 minutes or so per fly once you get the hang of it.
Another (perhaps more labor intensive) technique is to make a dubbing loop, snip the bou fronds off the stem and place the ends in the loop and spin. Makes a pretty fly with a different look. Might be a good idea to have some hackle or chennile underneath to help avoid collapsing in stream. I've only done it a few times.
Following the same idea of keeping the marrabou from collapsing against the current, I was taught another technique using an underbody of dubbing (or chenile as BS suggested) with saddle hackle palmerred over it. Next tie in your layers of marrabou.
The tying method I use for marabou flies was shown to me years ago by Dan Lemaich when we both worked at the old Swallow's Nest. It is also the way that Mike Kinney ties his marabou flies. Called the Spun Marabou, this fly uses only one nice full marabou plume.
Hook: Steelhead hook of your choice. I use Gamakatsu in sizes 4 through 1/0.
Wrap the hook shank with silver mylar tinsel. Criss-cross it with monofilament thread for added strength. Tie in a few strands of silver Flashabou right at the rear end of the return loop.
Trip the webby material from the plume and wrap it, tip first, onto the hook. This will place the largest fibers on the outside for a nice appearance.
Face the marabou plume with a neck hackle either the same, or a constrasting color and tie it off.
Preen back the marabou and the strands of Flashabou. Trim the Flashabou so that it is just a tad longer than the feathers. This makes it sort of wink when it swims through the water.
I have used the Spun Marabou for both salmon and steelhead for about twenty years. With its slim profile when wet and a fairly heavy hook, I have never found the need to add lead wire or heavy eyes. It sinks very easily.