If you want to sell your designs in the Spoonflower Marketplace, you must order a sample of your design. Typically a swatch on any fabric or wallpaper is fine, but larger sized designs may require more. The reason for the proof is that the colors you see on your computer monitor may come out differently when printed and there can be issues with your files that aren’t apparent until printed. Make sure to check that the color, image resolution, and repeat all match how the design should look. After your proofing order has been shipped and received, the option to make it for sale in the Marketplace will become available.