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Making a lifelike mask yourself is possible with silicone! These masks will feel and move like real skin and can be shaped in many ways. There are many YouTube movies on how to make silicone masks.
Making a realistic mask requires practice!
Because silicone is hard to paint the base color is often added to the silicone when mixing. Further coloring is done in very thin layers by using the same silicone in the desired colors. Often, the silicone is dissolved in toluene or thinnner to spray it with an air brush.
Note that addition curing silicone does not adhere well. It works best when you work on a still tacky silicone layer
Of course you can also make a hard plastic mask of poly urethane. Polyurethan is very easy to finish and rework.