OK first make your image in photoshop or whatever photo program you have. Print it on photo paper. Take your glass tile & glue it to the image. Coat the back with resin or whatever you prefer. Once the back is dry glue your bail (silver thingy) to the back. Use jewelry glue if you have it. If not super glue that works with resin should be fine.
OK I tried to pretend walking through the steps as I was doing this. Hope it's clear as mud. If not please let me know & I will try to help you!