I'd talk to Davidyr1, he did a lifecast on my face last weekend at a convention. Took 20 minutes and turned out great. He can tell you exactly which products to use.
Basically it involved a silicone release applied to the hair (eyebrows and eyelashes) as well as the general face. The a thin coat of a silicone paste, followed by a thicker coat. Then some plaster strips were applied to help the mold keep its shape. The plaster was removed, then the silicone was slowly peeled off my face and voila. A full mold ready for Resin.
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