Place Cushion Stone in Setting, pressing the bezel into place to hold the stone firm. Bend the prongs down from alternate sides to keep the stone centered. Use finger pressure or nylon-jaw pliers, to avoid scratching the finish on the back of the stone.
When prongs are bent down, use the burnisher to flatten them to the stone, and prevent snagging.
Use flat-nose pliers to open the loop on the earwire, and slip the setting with stone in place. Bend back.