"Mix 1 part flat paint and 1 part water. Add a dollop of wallpaper paste (the natural kind, called wheat paste). Mix in plaster of paris little by little as if you were mixing cake batter till smooth. Finish by adding a splash of milk to keep the plaster from hardening too quickly. Only mix a little at a time at first till you get the hang of the time it takes to harden and how fast you can get it up. Use a real stucco knife imported from Italy. You will not be able to get it smooth enough with any other tool."
"First of all, buy marble dust. It is available here. Mix it into any latex or acrylic paint; 50% paint and 50% dust. I use a pyrex pie plate as my pallet and mix with a plastic putty knife until all of the dust is incorporated and the mixture has the consistency of tooth paste."