Step 3: Carving the Clay Mold
This step is the most fun! Start in a corner and scrape out the clay toward yourself. You should go between 1/8th and 1/4 of an inch deep. Keep removing material until you are satisfied with the basic outline.
Now smooth out the impression with a smoothing tool. It looks like a small soft eraser on a paintbrush. Try for a uniform depth and clean edges.