Step 1: Drilling

Drill a hole in the top of the mason jar big enough for the light to fit through. I would recommend to use a hole saw attachment. I didn't have the right attachment on hand so mine is pretty bad.

Step 2: Hot Gluing

Only hot glue the top part of the LED to the lid. Make sure that the bottom part is still twistable or else the light won't work. Seal any holes with caulking or hot glue so water won't leak.

Step 3: Finishing Up

Pour decorative marbles into the jar. Add marbles as desired. Fill with water once your done pouring marbles. Screw on the lid and watch it light up! :D