Each of our products requires a high quality image for your product to turn out looking well. When creating your artwork be very mindful of your edges because the process we use means the edges will need to have at least a 1/4" buffer on any product. You don't want to put any text or crucial images right up to the edge because they would get cut off.
When you upload for custom artwork we have a guide that will show you approximately what your image will look like. This only works if you use a JPG as an upload. If you have PSD file ready to go and are confident then you can upload that image and skip using our guide or just save the image as a JPG as well.