Sprinkle a little of this ultra-hard powder wax on your base (or even just along your edges) and carefully tamp it down with a heated iron before applying your wax of the day.
It helps protects the base in cold and abrasive (icy, manmade, etc.) snow conditions to help prevent base burn, as well as increase the durability, and hardness, of the overlaying wax layer.
Use at snow/air temperatures of -15°C (5°F) and below.