Find a baseball cap at the thrift store, one that fits your head well and is deep enough to sit securely.   At the dollar store, find a ring of styrofoam where the supplies for flower arranging are located.  At the hardware or discount store, get a roll of ordinary, grey duct tape.;
,,  Make them mirror images of one another, since they will go on each side of the hat.
  Try different heights and angles for the horns.
 Cut a 12" piece of #10 common, household wire and double it. Hold the two raw ends and push the wire through from the middle of the horn, and having it come out at the base. Repeat with the second horn. On all four raw wire ends, circle and flatten them and enclose each in duct tape.
 Tape over the flattened wires encased in duct tape on either side of each horn. Criss-cross tape and flatten and mold with your fingers to make it lie flat. Use 6" Pieces of tape and spiral it around the horns, pressing and molding with your hands.
 Angle and criss-cross the pieces to stabilize the horns and incorporate them onto the hat, contouring, overlapping and molding the tape to the hat and around the base of the horns.  Use a lot of pressure to flatten and contour the tape to the hat.
, Lay the ball in place and cover it with another 1" piece of tape. Mimic metallic straps by using contrasting colored duct tape crossed over the front of the like a metallic band.  

,  The possibilities are endless.
Begin by assembling supplies for the helmet.
Cut the brim off the hat with scissors.

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Cut two five inch pieces from the styrofoam circle and taper and round out the ends of the horns with a serrated steak knife.
Test how the horns will look by holding them up to the sides of the hat using the seams in the hat as guides to get them symmetrically aligned.
Run wire through each horn to attach it to the baseball hat.
Tape the horns onto the hat using 3" pieces of duct tape you have torn in advance and lined up along the table's edge for easy access.
Wrap the entire hat, horns and all, with 12" pieces of duct tape.
Trim the hat with fur by hot gluing a strip cut from an old hat around the entire opening of the helmet.  

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For rivets, use scrunched up 1" pieces of tape.
Look up Viking head dress or Viking helmet for ideas on how to finish and embellish the helmet.
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