I am a novice at making jewelry so I was pleased to find this video which shows how to make a simple heart pendant and earrings. The demonstrator mentioned using wax paper or parchment paper, but I use freezer paper when creating my pieces because it has a coated backing and it can go in the oven. Not only that, the roll is much wider and is 75 square feet long. (objects to be baked need to be placed on the non-coated side) I cover my work surface with it and cut a small piece like the demonstrator did for underneath my working piece. This makes it easy to turn the piece around while working on it and when finished just place it on your cookie sheet (I use a dedicated cookie sheet) to bake.
I loved how she used another piece of clay to take the heart out of the mold. It doesn't distort the piece at all.