Air dry clay, or paper clay: IOD air dry clay is an air dry medium, and one of the favorites to use with IOD designs moulds. Like most paper pulp based air dry clays, some shrinking, warping, and cracking is inherent, these qualities are great for a distressed, authentically vintage look. The most popular way to apply moulded pieces is to remove them from the mould while still moist, and adhere to the surface with the appropriate glue so it conforms well. For vertical surfaces, use a piece of low tack tape to hold it in place so it doesn’t slide.
On releases: Most of the time a release is not necessary and the casting will come out without the use of a release, however, if you are having trouble with the material sticking (more common with clays than resins), a light dusting of simple cornstarch or arrowroot will help.
Instruction video link - https://youtu.be/8TRlzR5fFI0list=PL3M31Z09RMJ4oWoiBulcqOtIm_hGjW7OS