Now that Jean has learned how to sculpt a face she asks:
How do you make a mold?
There are different mold making products on the market today. It depends how serious you want to get about making molds. There is an on-line class taught by Jeff Goshon (Sherry's hubby) on making resin molds - which would be good if you wanted to go into production and sell your molds. He will also make molds from your sculpts.
You can use regular polymer clays to make molds. Just knead up some clay and press your face into it (be sure to use a release agent on the original sculpt). Then bake. You can use Super Elasticlay, which is a flexible polymer clay that some artists like for mold making. That is what the MoldMaker product you can find in the craft store is made of.
I have used Alumilite's 'five minute putty', molding material that is used in the hobby industry. It is a two part product - when you mix it up you have five minutes before it is 'set'. To use it you basically mix the two parts and then press your sculpt into it. After it is set up you pop out your sculpt and, voila, a useable mold! This is some type of silicone or rubber. It makes a really flexible mold.
This should be enough to get you started .... have fun!