Before I go off, lets start by saying Fishio is that all we have to go by here is the photo and I would have guessed that the fish in that shot was going to be bonked. In fact based on the blood on you hand, I thought you had killed it already.
Fihio...you should never touch a fish in and around the gills, it looks like you have got a pretty good hold on it there. As well, slime coats protect fish from disease and for a fish like steelhead that can return to the ocean after spawning, it is very important to disrupt it as little as possible. Your are, your hand, your leg, they all look to be in contact with the fish...not the best thing for a fish your are going to release.