[mjohnson]

Snowboard, skis, whatever - the idea is the same.

First check that the base is flat. The very last thing that you want is for the base to be concave or for the edges to be above the base material (when flipped upside down). Such a condition would make the board "railed", and it'll turn like a locomotive...

If you've got that problem, get a stone grind at your local shop.

Once you're flat, you'll pretty much only sharpen the sides of the edges. If you trust your feel, you can do it freehand. There are cheap guides available to make this easier.

You'll need a sharp, new single cut file to sharpen your edges. Pick up a diamond stone to knock down any nicks and burrs from rock strikes (the deformed metal will be harder than your file and will therefore screw it up).

Always run the file in the direction it was meant to. Don't rub it back and forth.

Enjoy the smugness of sharp edges - or move somewhere with only powder...