Gear is most important for a warm, dry and enjoyable hunt. Especially good clothing. Everyone else has said those things.

After you have done all the things you can do to prepare for the hunt mainly getting gear and exercising for endurance. There's one main key left for when the opportunity arises. That is to pratice shooting. This is where alot of hunters come up short in elk hunting. Find somewhere you can shoot up to 250 yds and know your rifle. Judging distances out west is troublesome for alot of people maybe a rangefinder would be helpful. What ever your comfortable with but I tell my guys to sight in for 200yds. Don't by all means sight in for any distance futher than that. 200yds sightin is great for the western states and more open country less guess work and not much difference at a 100yds in today modern calibers. But main thing shoot alot before you come. And goodluck.