Snow flock, a mixing cup, PVA glue and something to mix with (I use coffee stirrers or lollipop sticks personally).
I mix the snow 50/50 with the PVA glue and add water until I get the desired toothpaste/porridge consistency so it's not runny but not like dough.
Once you have the mix looking right, take your base (using an unpainted junk base for this example) and using your mixing tool, drool a small amount of the mix where desired.
I made up half a plastic disposable cup's worth, which if coved up properly should last a week or so for wore applications. if it dries out just add a little water.
So that's my (Very) rough guide to how I do snow, hope it helps someone out but if not at least it make me look like I blog alot ;o) and it's a nice break from not painting my guard ;oD
Here is some pics of the ogres I used this method on: