First, I printed the picture of the skull (I got this one ready for you to print both at once just scroll down). Then I cut out the paper and used jewelry glue to adhere the image to the back or flat side of the marble. I also stuck a large jump ring at the top of the skull and wedged it into the glue. Now, they do make jewelry glue that works specifically for glass which will be handy if you can get some.
Second, when that dried I laid the bead flat side down on a piece of wax paper and glued a ring of ball-chain around the outer edge in the back. Let it dry very well.
Third, I attached the earring finding to the jump ring at the top and then looped this cool little winged heart bead through one of the open spaces in the ball-chain at the bottom.