Draw around your glass marble bead on to some scrap paper.
Cut your template out.
Take your bead and your magazine, cut outs or photographs and find an image that works well.
Take your template and draw around it on to the image.
Cut out the image.
Glue the top of the glass marble with clear strong glue.
Stick the bead down on top of the image and leave to dry.
Trim off the excess image and then stick to a magnet or jewellery.