Fortunately the plaster cast from the mold of the anatomically correct skull came out successfully! So once we soaked it in water and removed it from the jacket, I used various tools to scrape off the extra bits of plaster and to carve more detail in to various areas, such as the teeth. I then soaked it once more in a bowl of water for 20 mins, and whilst it was in there used a piece of sandpaper to gently smooth over any marks that the tools had left on the surface. Once soaked and moist, I used clay to build up areas around the eyes and forehead that would make it look more like a typical Mexican skull.