My stepson had to do a project for school involving making a mask for Romeo and Juliet. So I walked him through the project by making my own mask (his ended up being black and purple).
Anyway, since we had to do a quick job of it, this isn't as elaborate as some of my other masks. Took a only a few hours to make. The base is one of those plastic half masks you can buy at craft stores, over which I decoupaged some specialty paper that had gold fibers woven into it. The back is decoupaged with some slightly textured black tissue, soft enough to wear against the skin.
Then I sealed it with a clear varnish and used hot glue to "draw" the raised patterns and apply the braid trim around the outer edge, the feathers, ribbons, and gold skeleton leaves (usually used for scrapbooking, but I love the fragile looking texture they have). The jewel in the middle is a piece of costume jewelry (earring) that I cut the back off of and glued in place. I used Renaissance Gold Leaf paint on the cooled hot glue design.
The mask is actually really comfortable to wear, very solid (no peeling, and ties on with the ribbons trailing about two feet down the ornamented side.