Harrison Krix, aka Volpin Props, is someone whose work you should be very familiar with if youāre a regular Kotaku reader.
https://lastchance.cc/the-very-best-in-cosplay-volpin-props-5890417%3C/a%3E%3C/p%3E
Heās posted a thorough development report on how he made the thing over on Instructables, which he says can be used not just as a guide to help you make your own Skyrim helmet, but to make your own anything helmet.
Creating Helmets and Armor from Videogames for Fun and Profit! [Instructables]