With Elk, Deer or any big game animals. I'm sure everyone has heard not to skyline yourself. But I will say it again, right before you get to the top of that ridge you took so long to get to, stay low, get on your gut if you have to and peek over that ridge before you go over the top, and decide to glass.
Just this past weekend, I made that common error of going straight over the top and there was a large 6x6 Elk standing just on the other side. It would have been great to see him before he saw us as he bolted dissappearing into the thickets. Seeing them before they see you will give you a chance a lot of times to pattern that big boy. Don't blow it and take your time.