I'm working on a survival story and want to make it authentic. If you were stranded on a mountain trying to get down as fast as possible, what would you do?
EDIT: What if this was after a plane crash on a desolate snowy mountain? Would it be possible to fashion some kind of combination from debris and nature to propel down the mountain?
From your heading I gather the mountain in your story is covered in snow.
If the slope allows it, then I'd skid down on my behind. Grab something like a suitably formed stone to be able to perform a self-arrest. Any kind of skis you could expect to build up there would perform far worse.
The technique @helm recommends is (at least in this neck of the woods) called a "Glissade". It is essentially "a method of descending a steep snow-covered slope via a controlled slide on one's feet or buttocks". I have heard of people using other items to assist in a glissade by using them as a sort of sled, a backpack or as in Ed Abbey's Desert Solitaire; a large flat rock.
If I were you I would spend some time googling this term as it is a more realistic way to quickly improvise ones way off a mountain, rather than taking the time to attempt to fashion proper skis.
Now, depending on the type of story you're writing, you could have your character just strap a couple felled logs to their feet at let fly! AKA Paul Bunyan.
