If you're like me, freak out, start crying (even though it's a completely fictional situation) and rambling, "I don't know! What's the humerus?! Is he dying? YOU'RE DYING! DON'T LEAVE ME!"
Or, if you're like one of the BA Wilderness Medicine Club members that represented PCOM at the annual Mid-Atlantic MedWAR in Newport News, VA, you check his ABCs, put pressure on the wound, and use anything in your bag (or anything you find around you) to stop the bleeding. Then you mountain bike, canoe, trek through the woods, and hit checkpoints along the way which test your academic and practical knowledge of wilderness medicine.