You will need the parts you want to make a mold of, some vegetable oil, and green stuff. Then, take the parts that you want to mold, and paint them with some oil, making sure to completely cover them so the gs doesn't stick to them. Then simple cover the details you wish to make a mold of in gs, wait a couple days and pull the dry gs off. Now you should have the reverse of what you started with. Trim it down with a hobby knife if need be, and when you want to make more parts, put some vegetable oil in the mold, and fill it in with more gs, and when it is dry you will have a copy of the orginal.