Draw out the designs you want for your pottery on a piece of paper. You can draw any image you would like to appear on your art piece.
Cut out the outline of the image you drew on the paper. Using a razor blade or Exacto knife is going to be the easiest way to stay true to the outline you created. If you use straight lines in the design you can cut along a ruler to help steady yourself. Make sure there is a piece of cardboard under where you cut to prevent damaging the table surface under the paper.
Wrap the piece of paper with the cut out images around the pottery. Tape the design down so you can paint on the gloss without holding the paper on.
Paint over the stencil with your gloss of choice.
Allow the gloss to completely dry before removing the stencil. If you do remove the stencil too soon you can smear the design you painted on the pottery.