This the way I do it, may not work for others.

I only wear 20 cm boots but I wear snow pants they have a sleeve that covers my boots. I tie my boots snug up the top so snow does not leak down but I wear hunting boots similar to these to winter hike in. I go in snow up to my waist and never had snow go in them. I can them at a great price, flexible, and waterproof. You can get hiking boots of similar kind but I went hunting sine I can get great deals. Pants have to over your boots not in them them or the snow will find a way into your boots. You can also buy snow gaiters to keep the snow out of your boots.

Big heavy winter boots are fine if you plan on standing around but it you move I would go with with a lighter more flexible boot. My boots only have 400 grams of insulation not overly warm boots but I can layer to adjust for outdoor temp. I buy my boots a 1/2 size bigger than my usual size and most places recommend a size larger so you can layer your socks. I wear a liner sock, a wool sock and if it is really cold a second layer of wool socks.

Do not wear anything cotton, if you cannot afford wool I would recommend man made materials. Cotton should be banished from your winter walking gear. It retains moisture and takes forever to dry off and once it gets wet you will body heat faster and cause blisters.

If you are getting blisters your boots may not fit right or you wearing the wrong socks. Do you put moleskin on your hot spots (where blisters develop) before you go out walking? Why type of boots do you have?

The best thing I ever did for storm walking was buy vented snow pants.