Snow Paste
There are a lot of different snow texture pastes out there. Here is a chart of different solutions that you can purchase.
Now you don't really need to spend money on these. You can make your own version with items you might have at home. This is a homemade texture paste recipe I found recently on the blog, Such a Pretty Mess. It is made from a combination of talcum powder, glue, white paint, and water, and can be stored.
1/4 cup baby powder or baking soda
1 tbsp PVA craft glue or Mod Podge
1 tbsp white craft paint.
water to mix to the consistency of toothpaste.
The finish is nice and smooth - and it is relatively flexible. You can use either a brush or a palette knife to apply. The baby powder/baking soda is fine enough to resemble a fluffy snow texture.
Mixing the Ingredients.
Applying the Mixture to a base.
Let the mixture dry on the base.
Here is the finished base.
Now if you want to give your snow some shimmer add some diamond dust fine glitter, or make a very very watered down wash of light blue metallic paint just enough to shadow the snow and spread that metal flake.