The first thing I always start with is sketches. Sometimes I'll draw an idea over and over for years before it will look just right and I'm ready to carve it. Other times I will know exactly how I want the piece to look and all I will draw is a quick thumbnail.
The next step is to form a lump of clay (any clay that hardens will do - in this picture I am using polymer) into the shape of the stamp. The dark purple disc is a glass sun catcher, but I often use small glazed tiles as surfaces to work on. Then I draw the design onto the clay backwards. I can do this now without tracing my design with pencil and pressing the clay onto the paper to get a reverse image, since I've done so many.
Then, I slowly begin scraping away the design. This part is tricky. The rule is, the deeper the marks, the more they will stick out in the design, so really faint, shallow marks will look far away. The first designs I made were flowers, almost like lace and they translated well in this format. The hardest things to make are faces. I avoid these as much as possible, but I like to carve mermaids, so I know there will be a lot of filling in and recarving.
When I've finished carving, I harden the clay (curing polymer in the oven, firing stoneware in the kiln or air drying - depending on the clay) and then I get to the fun part - testing the design! I use water as a resist for polymer and olive oil for other clays, then press in clay to see my work. Sometimes it's a lovely surprise, other times, its a deep sigh, knowing it will have to be made over, with modifications. This piece is good and I'm pleased with the depth and little details. From this point, production begins and either soft wax or metal clay can be used to press into the stamp. I use both materials, depending on what metal I want to end up with. I used to use just metal clays, until the price of silver clay tripled, making it too expensive for production.
This type of mold wears out eventually, so one can only pull a finite amount of copies. I have mixed feelings about this aspect. It's sort of precious, only getting so many copies, but since the mold is the master, its also a little distressing. I'm very much like a dragon and like to have lots of piece, in case I might run out.