Great advice above from
@BlakeA and it’s worth mentioning again about good boots.
I’ve always thought elk hunting is about legs and lungs, start running or brisk walking every day, as much as you can. Make sure you’re doing it on uneven ground instead of pavement, those stabilizer muscles need to be worked. Walk in the ditch or the grass.
I also think beyond gear and physical ability, keeping positive in your head is very important. Elk hunting can be extremely difficult, and also things can happen quick and in weird places. My first two seasons in Montana 2006 and 2007, I shot a cow in the last few days of the season, and my first bull on Thanksgiving Day respectively. I had hunted hard through the whole archery season and gun season. At the time I worked three day weeks, and had four days a week to hunt. Mind over matter.
If you can swing it, take two periods off to come out, if it were me, I would come hunt the first week of the season and the last week. That is if you are rifle hunting, if bow hunting, I would come the middle to end of Sept.