My girlfriend and I decided to make papier-mâché Halloween masks this year.
The process included making plaster mask forms from lifecasts of our faces and making a huge mess. I had prior experience with mask making before undertaking the projects but had never done lifecasting before. The biggest problem we had is that the instructions on alginate boxes are not only terrible, they are often just plain wrong. I recommend playing with small amounts of alginate and water to find the ideal ratio for a particular application. My favorite papier-mâché methods and recipes can be found over at UltimatePaperMache.com. I highly recommend watching her mask making videos before attempting to make your own masks. Her tips have saved me a lot of grief.