Protect your work surface by covering it with newspaper or drop cloths. Place the stepping stone mold on the work surface. You can use either purchased stepping stone molds, or use plastic planter saucers for round stepping stones. Mix the concrete according to the manufacturer's directions and set it aside.
Spoon the concrete into the mold until it is about half way full. Cut a piece of screening to roughly the same size as the stepping stone mold and place it on top of the concrete. Continue filling the mold with concrete until full. Tap the mold gently to remove air bubbles. Allow the stepping stone to dry for about 45 minutes.
Cut your photo to the same size and shape as the piece of glass you will be using. Coat the glass with clear-drying glue, and place the photo face down on the glass. Allow the photo and glass to dry for at least 15 minutes.
Place the photo and glass face up into the stepping stone mold (the concrete must still be wet). Add any additional embellishments if desired, or write in the concrete using a pencil or dowel rod. Allow your stepping stone to dry for three days before removing it from the mold.