Unlike salmon fishing, steelheading is a "hunt". You have to move around a lot (and I mean A LOT) to have any kind of hope at hooking into the elusive "fish of a thousand casts". Their numbers are small, so the real issue is to find the fish.
When you do, any terminal tackle presented within its striking zone might work. Steelhead are stupid and glutonous. They will hit anything you offer them, especially if it has scent and flavour. Flies are much less productive than bait or metal. Some fly fishermen often go several seasons in a row without connecting with a steelhead. But then again...when it does happen, it is a moment of glory!
Steelheading defines us as river anglers. The cold and wet days, endless hours of casting without a single bite and the tough retention regulations all contribute to weeding out the opportunistic anglers who are out in full force only when the prospect of catching fish is good. Steelheaders are a different breed. They are out for the sake of being out - catching a fish is just a bonus.
As you walk many miles along the river, look for structure where a steelhead would feel safe (deep pools, ripples behing larger boulders, log jams, etc.). Try a couple of casts with one terminal tackle, and then change your presentation. Never spend more than a few minutes in one spot. Never cast the same terminal tackle more than a few times in the same spot. If a steelhead is there and wants what you have to offer (e.g. a roe bag or a purple bunny leech), it will hit within a few casts. If it doesn't, change your offering. Repeat. And keep moving. Don't sit in one spot waiting for the fish to come - they won't.
Few people catch a steelhead in their first season of fishing for them; some have to fish several seasons before they catch the first one. It is an affair of three P's: preparation, patience and perseverance.
Tight lines.