If you want the horns to be mounted nice and solid, it's a good idea to make some flanges:
Just to keep some weight off of your neck, you might want to hollow out the horns:
Me so Hoh-nee baby:
Now let's make this fit a little better.
Get yourself some rubberized foam.
(I like the rubber pipe insulation, it's easy to find and work with):
Cut it into 2" strips:
Spray adhesive onto the pieces (Not into the helmet, it makes a meep of a mess.) then carefully line the helmet so that it fits yer dome securely:
-Oh, Yeah. I noticed the leather was tearing out on the cheekplates, so I'm recommending you rivet in some hinges like this^.
The last step is to deck your helmet out in some fur.
You're a savage, damnit. Go kill something fuzzy!
Wait, no. PETA's gonna be all up in my meep if you do.
Go back to the fabric store...(Yeah, I know it isn't meeping manly. Suck it up.)
...and get some... :shameface: ...faux fur.
Now measure out the flanges and add an inch of overlap for gluing:
Trim the fur off the overlap with scissors:
Then hit the overlap and the backside of the other end with spray adhesive, and join them up:
And there you go; Horn Pubes:
This is the basic method. You can add some fur to the aventail (Or whatever the thing in back is called) or skin the whole helmet in leather or make any of a thousand variations that tell the world: "I'm so-and so and this is my meeping hat."
You have the skills now.
Make use of them, or when the zombie apocalypse happens (and it will happen)
You'll wish you had.
Thanks for watching.