Add a small amount of Diamond Glaze to back of glass circle. Spread around with tip of dispenser or toothpick. Press gently on photo to remove bubbles and hold for 30 seconds. *Note: do not wiggle it around too much as that will smear photo ink. If you make a mistake (or see bubbles), don't worry - Diamond Glaze is water soluable, you can wash off the glaze and paper from the glass piece and try again. Allow to dry overnight.
Using X-Acto Knife, cut paper and extra dried glaze from around glass piece.
Add a small amount of E-6000 adhesive to the inside of pendant (once this dries- it can't be undone) and press glass piece with photo into pendant. If needed, tap (may need a few taps) glass piece into pendant. Remove any extra glue/paper with X-Acto knife that may have pushed out around edges of pendant. Allow to dry 4 hrs.
Place pendant on any chain, ribbon, or key ring you choose.