I like dry brines best. start with a good product, bled and put on ice, well cleaned and filleted.

rock salt
dark brown sugar
fresh dill

I also like mine skinless, it speeds up the brining and drying processes. Sprinkle rock salt, brown sugar and dill in the bottom of a plastic container. Lay the fillets on top of the mix, then repeat the mixture over the top of the fish. Place another layer of fish on the first layer and cover with the mixture. I repeat the process until all the fish is in the mix. ( try and keep the thicker pieces at the bottom of the stack.) Skinless fillets sit covered in the fridge for about 4-5 hours. Skinned 6-7 hours. Smoke with alder/apple until its as dry as you like it. I like at least two pans of alder to one apple. It is a very consistent brine and always turns out good. I also have experimented with using half the brown sugar (sprinkle lightly instead of cover the fish) then put some maple syrup over the top of the sugar. This is good if you like sweeter fish. Sockeye is my favorite to smoke.