Right now it's about covering water. Learn the river, fish entire runs and what's in between. The Vedder is unique because of the volume of fisherman. Pay attention to the spot if you see a fish caught, if there was a fish there, there will be one there again.
Steelhead are stupid, it's just a matter crossing paths at the same time.
For me, by March, all I'm doing is checking out places I've caught fish or seen caught.
I caught last years first fish where I had seen somebody else catch one. Was at the same sunken stump this year to get my first as well.
Don't overlook riffles and tailouts. Steelhead will sit way back in the tailout when pressured and or move into the fast stuff. Don't forget pocket water. If you poke one and miss, leave it to rest and come back later. It'll be there. A lot of times steelhead will pair up, and sit in the same slot.
Hope this helps a little.