Getting cold feet? Not only is it unpleasant, it puts your feet at risk for frostbite. Start on the inside with plush liner socks designed to wick moisture and stay warm when wet, made from materials like wool and nylon. (Never wear cotton socks in cold, wet conditions!)
On the outside, be sure you have snow boots that are waterproof or water-resistant, depending on how wet the conditions are. Winter boots should be lined with Thinsulate® insulation for somewhat cold temps, or thick, removable synthetic liners for frigid temps. Boots with removable felt or foam liners make it easy to dry the liner when you get back.
The coldest-weather boots are usually temperature-rated. I own two pair on that is more generic for warmer winter days shoveling the driveway etc. I also own a pair that is rated at 30 below zero.