- 1). Measure out the amount of plaster of Paris needed to make a mold. The general use for most brands of plaster of Paris is 1 part water to 2 parts plaster, with a yield of approximately 1 1/2 cups of the finished product.
- 2). Pour water into the mold to the level you want the plaster, then measure it out in cups. For instance, if you want to make a mold of your handprint in a pie plate, you would pour water in to the depth you want. If you used 4 1/2 cups of water, you would then need to use 6 cups of plaster of Paris and 3 cups of water.
- 3). Measure out the dry plaster into a plastic bowl and make a well in the middle. Pour in the water all at once, and stir until the mixture is smooth.
- 4). Pour the liquid plaster into your mold slowly, starting with the lowest areas and filling in all the spaces. Use all the plaster you prepare, as it doesn't store well.
- 5). Allow your plaster of Paris mold to sit undisturbed until it hardens. Carefully loosen the edges, and allow the plaster to fall out. Make sure you catch it.
- 6). Use prepared plaster bandages to wrap around fully inflated balloons to make easy pinatas. Dip the pre-rolled bandages in warm water, allowing them to soften before wringing gently and unrolling onto the surface of the balloon. Use a single layer, and allow it to dry completely before popping and removing the balloon from the top.
- 7). Make free castings by pouring mixed plaster into animal tracks or other indentions and letting it harden.
- 8). Fashion small bits of jewelry by filling tiny plastic molds with plaster and painting the hardened objects to use on children's bracelets and chains.
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