The biggest bulls I have killed, or helped to kill, were all taken during stretches where I was sleeping on the mountain among the elk. Well, not right in the herd, but downwind a few hundred yards. You’ll need special gear to bivy hunt, including a superlight tent, sleeping bag, pad, food, stove, and so on. Research the gear, purchase what you need, and make some practice camping trips during the summer with it. That way you’ll be ready to deploy your camp at night when you are cold and tired, and then pack it before daylight so you can sally forth in pursuit of that bull that bugled your name all night. It’s one of my favorite experiences: sleeping on the mountain, stars overhead, bulls bugling in the distance. And it’s absolutely one of the best ways to kill elk.