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If it helps, you can erase the lines you drew when tracing your photo. Then use a pair of scissors or a blade to cut along the inside rectangle (which you drew in the previous step) and the outside border of your frame. Now you have the foundation for the front of your picture frame! It can be tricky to cut the inside corners, but it’s ok if they don’t look flawless. You’ll be covering them up with fabric anyway! This will serve as the back panel for your frame. Trace the frame, or mark out its dimensions onto another piece of cardboard, and cut it out with scissors.  You can use the same cardboard, but a lighter-weight version would also be fine if you’ve used corrugated cardboard for the front. Or, if you’ve used lightweight cardboard for the front, you can use corrugated cardboard for the back to provide some support. With the wrong side of the fabric facing up, place the front frame piece down onto the fabric. Center it as best you can. If you want your frame to stand up, use a leftover piece of stiff cardboard as the frame stand. Cut a rectangle the same height as your frame, and fold down the top by 1⁄4 to 1⁄2 in (0.64 to 1.27 cm). Then apply glue to this folded piece and stick it onto the back of the frame. Allow the glue to dry completely before standing up your frame.

Summary:
Cut along the innermost and outermost lines. Cut a second piece of cardboard the same size as the open frame. Place the open frame onto your piece of fabric. Glue a folded piece of cardboard to the back panel as a frame stand.