When silkscreening clay, even though the paint dries, it is relatively fragile on the surface of the unbaked clay. If you want to shape the piece into a curve, this trick makes the job easier. Make sure the paint is dry. Then burnish a piece of Clear Deli Wrap or even Saran Wrap onto the surface of the silkscreened piece.
Lift the clay with the plastic burnished onto the surface, position on the curved baking form, and slowly press the clay onto the form. When shaped to your satisfaction, slowly pull back the plastic. Bake.