Here is my first attempt at a "ViewMaster" card. By using the "center point" setting on my Cricut Expression, I was able to place the cut-out on the card front where I wanted it, plus any size I wanted it. If you don't have a Cricut, any circle cutting system will work.
Original Viewmaster Card design by Kyla Maestas (Splitcoaststampers.com). ViewMaster is a U.S. Trademark of Mattel, Inc.