How to create snow material
From Post-Apocalyptic RPG wiki
This is a short guide on how to make interesting snow material. In nature, snow is rarely just white, it has this blue feel to it. Just look at this glacier picture from wikipedia, or this Commandos 2 screenshot.
A completely grey snow is boring and not that believable so what else to do, but to add a blue tint to our snow material :) It's not enough to simply make a bright blue material, since the shadows and darker parts need to be blue as well. In addition, shadows cast by other objects which fall on snow, should be blue as well. For this, we use a node setup of course :)
Below you can see two images, one shows the original greyish material which could never be even mistaken for snow, while the other shows the same material, but using our nice node setup to make it brighter and bluer. Naturally, the material can be further tweaked, but hopefully this gives you a general idea how to approach this problem.
And here is another example, showing how a shadow of a non-snow object becomes blue when it falls on the snow.
This is the blend file with the snow material and the node setup.