The first time you see an elk on the ground, when you're used to deer, you'll think ...."Now what?!"
They get big. Have a plan ahead of time on dealing with a critter that big. If legal where you're at look up the gutless method for quartering it up. This will likely be the easiest thing for you to do unless you're on a place that allows vehicle access etc. Of course if your buddy has experience, just follow his lead.
-Jake