Majora’s Mask is one of the most recognizable things in all of the Legend of Zelda games. Instructables user magicman391 built one, and he began by making a computer model of the mask in Rhino just to get the placement of each section down. He did a clever thing and split the mask into three segments in Rhino so he could print a top view of each piece and put it on layers of pink foam. This allowed him to easily get the right shape. Here’s how he proceeded from there:

Now most people know pink foam is good for doing rough shapes and has no real permanence especially with the introduction of solvents sooooooo I coated the foam with a layer of my favorite material of all time… epoxy putty, specifically in this case I used Apoxie Sculpt.

Next came the fun part (I jest since bondoing and sanding takes a long time and is very repetitive) I apply a layer of bondo to the surface to even it out, followed by immense amounts of sanding, then repeated this process several times. I followed the final sanding step of bondo with spot putty to fill in the small gaps, then of course sanded that smooth.

Read more at Instructables.