In my experience, the best way to keep your feet warm and dry is to start with a good sock. I prefer a sock with at least a 50 percent wool blend. Stay away from cotton — cotton fibers crush when wet, wool fibers don’t. Wool fibers maintain their shape, and maintain the insulating air spaces between the fibers.
Then you need a good boot. Personally, I chose the Danner Acadia 8" Gore-Tex insulated. Stay away from the $40.00 K-Mart specials — get yourself a good boot with solid construction, good soles, and a whole or partial leather upper. The more water-proof, the better.
Also, start to get in the habit of shining your shoes. Use good old fashioned paste wax — Lincoln, Kiwi, etc — because with that type of shine, snow and ice can’t melt or seep into the leather, saturating it and soaking into your boots. If there is a nice coat of wax on the leather, snow and ice just slide right off.
Finally, when you are wearing your boots, your feet sweat. I don’t care who you are, they sweat. Over the course of your shift, the perspiration soaks through your socks and into the liner of the boot. If you don’t dry the boot out, when you put it on again, that dampness will make your feet cold. So buy a boot dryer! They are seasonal items at most sporting goods stores and retail for about $20.00.
When you come home, put your boots on the dryer, and the dryer will slowly dry the boots out over the course of the night — nice and dry for your tour of duty the next day!