Trace the outline of your cake pan onto a piece of wax paper - then cut around the outline. Write or Trace your letters (if you are doing a design on your cake be sure to place the letters on the paper in the spot you want so you don't loose your design) onto this paper and gently lay over your frosted cake. Prick around the letters with a toothpick - then remove the paper and pipe your letters over the little holes in your frosting. NOTE: Frosting should dry before placing the wax paper on top. This method also works for pictures/designs too!