So Im making my very first costume. I decided to go with a mkIII iron man using the pepakura method. I made the mask and ive gotten through the strengthening stage and started applying the body filler. But as i get further along im trying to figure out how im going to make the jaw attachable and detachable so I can take the helmet on and off. Ive done a lot of research and I cant seem to find any ideas. Can anyone help me out?
Here are some pics of my work
Here are some pics of my work

