THE PROBLEM: the clay keeps lifting out of the mold as you are pressing it in. WHY THIS IS HAPPENING: this generally happens only with very shallow molds as there is not enough depth to "grip" the clay. SOLUTION: wipe your fingers on a damp cloth before you press the clay each time. This forms a barrier between the clay and your fingertips and stops it sticking to you. Or try a light dusting of corn starch to keep your fingers from sticking to the clay as you press clay into the mold.