Colorado

If you haven't already, start taking the pills for altitude sickness as it is the quickest way to ruin a mountain hunt. Go easy the first couple days for the same reason.
Calling, setups, hunting methods are very similiar for elk as for spring gobbler.
Good boots and many pair of fresh socks to keep the feet dry and healthy.
It will probably be cold in the morning and quickly warm up into the 70's-80's during the day so be prepared to change clothes as the day wears on and take sunscreen.
Don't drink the water.
I'am jealous, have fun.
 

i was out there 2 years ago fricken awesome! I am not sure but I think, dakota can correct me steamboat springs is low. but still higher than you may be used to. i was at 13500 and we did have some guys with altitude sickness. the weird thing is its hot here but when i went "same time " 2 years ago, it dropped into the 30's at night our dishrags were frozen when we got up. so.... my advice good boots good pack good gps. when you hike out in the am it will be cold by the end of the day you will be sweating your sak off. stay hydrated. guided or un guided ? pack a good knife MRE's are a good idea a good lenth of rope 100 foot, change of socks, save room as you strip off, good scent blocker, a good wind indicator, and a hoochie mama cow call. btw colo allows you to carry a handgun while archery hunting. just sayin