Step 6: Begin to cover the frog with your paper mache clay. Cover only as much as you can while holding a dry area of the frog. Then allow the clay to harden in a warm place, and finish the rest. You’ll need to support the legs and fingers while adding your clay to these areas. A very thin layer, 1/8 ” thick, will be enough. Smooth the clay as much as possible with the flat side of your knife while applying it to the frog.