Method of manufacturing a substrate with a cut thermal film comprises obtaining an input digital image of a design to be transferred to the substrate; storing the input image in memory; rendering design elements of the design as a single output image; based upon a bleed size value, a maximum number of negative areas, a maximum number of positive areas, and attribute values: resizing the image to include a border for bleed; filling transparent areas of the image with the substrate attribute values; creating a cutting path; creating a mask image; inverting the mask image; modifying the mask image to adjust fill areas around details, to limit negative areas to be less than the maximum number of negative areas, and to limit positive areas to be less than the maximum number of positive areas; creating cutting path data in memory as a vector path outlining the mask image.