Cut out a piece of wallpaper that covers the entire front of your frame. Pour a good amount of glue onto the frame. Lay the wallpaper flat on a table. Put the front of the frame onto the back of the wallpaper. Press it down. Cut an inch outside the edges of the frame to get an exact size of your wallpaper. The extra inch will allow you to fold the wallpaper over the back to secure it. Cut a slit at the corners so you can fold it over tightly. Tape the excess inch to the back of the frame.
Make four triangles in the opening of your frame by cutting an "X" through the middle. Stop short of the inner frame edges so that you are only encompassing the area where the photo would go. Fold each triangle to the back of the frame. Cut them where they overlap with the opening for the photo. Secure the flaps to the back with tape or glue.
Glue a piece of wallpaper to the back stand or to the opening where the photo is inserted. Cut around it for a perfect fit.