Replying to What do you wear on a cold day?

Hey! I'm just wondering what should I do when it's like -25/-30 concerning my outerwear. I don't own a solid jacket that is warm and I'm thinking about probably buying a insulated jacket. On the other hand, I thought that maybe a good thermal under my jacket which is only water and wind proof (a shell). What should I do? Btw atm my coat is a sabek and it's the best for like early skiing and spring time.

Tell what do you put under ur shell if so!