For the preparation of silicone rubber, which is scientifically called polydiethylsiloxane, you will need quite an ordinary household chemicals: water glass and ethyl alcohol.
Prepare the conditions for work and a suitable container, preferably plastic. Pour in a container of equal proportions of water glass and ethyl alcohol. Gently mix the components by using any tool, for example, spoons or wooden sticks. When the solution thickens, it can be brought to the desired state, just flexing hand. In the vessel formed a dense mass of white, which over time will become similar to clay.
When the mixture starts to solidify, mold it the desired shape. You will succeed without any difficulty, as the resulting substance becomes soft and plastic, it looks like rubber. Having achieved the desired shape, leave it for a while to give the final set. Silicone rubber will harden and the shape will become elastic and less susceptible to deformation.
If you want to copy an object, it is better to purchase liquid silicone in the store. It contains special admixtures that make it freeze slower, so it is easier to cast the desired shape. For a mold take the container, place the sculptural clay and place the object you want to copy. The container should be free of cracks, and both sides should be removable so that it can be easy to disassemble and remove the silicone mold.
Fill the container with silicone material from the edge. After curing, the top, carefully remove the clay In the container will remain half-filled with silicone figure. Repeat the pouring with the other hand and then disassemble the container. The model is removed, and you have remains in the hands of the silicone form, which can be used to reproduce the same thing many times.