1st time fly fishing salmon river

Welcome.  I use a pretty standard set up from what I have read and seen on the river.  9 foot 12 or 15 lb tapered leader tied to a #12 black barrel swivel then tied to a 4 foot piece of 10-12 lb flourocarbon.  Sometimes I cut about a foot of the leader if I'm fishing smaller portions of the river, but the rest of the setup is the same.  Just an FYI...Cabela's has (or had) a 12 pack of leaders on sale for 14.99 in select weights.  I was able to get 10 foot 12 lb, but the only issue is the tapered leader is 8 foot and there is a 2 foot piece of flouro tied with a blood not.  Great price, but not sure how they will work on the river.  Guess we'll find out in a 10 days. 
Everyone has their favorite flies.  I use Estaz flies size 6 or 8 in 10 different colors, Salmon River Fleas size 10 in orange or pink.  I tied some "jawbreaker" pattern (as seen on NY Fishtales site) to try this year, plus single Reel Egg patterns in a variety of colors.  And I always carry some large stonefly patterns and wolly buggers in black and olive.
Good luck!

make sure u have, at least, felt shoes. korkers/ cleats r better. the SR can be deadly slick