Once you are done with transferring the design on to the stone and it has completely dried off, then ensure that you cover it with a protective coating so that the design is not disturbed or spoiled over time.
colored pencil on rocks! (looks like dichroic glass!) SBG thinks you can spray on waterproof sealer and spot them into strategic places in the garden or among potted succulents. Thomas since you love you some colored pencil. and garden.