Preferred delivery method of all artwork is a vector created digital file with any type converted to outline/curves.
Screen Printing / Plastisol
Photoshop or other Photo Editing or Scanning programs
Remember to always create/scan art in these programs at a high resolution - at least 300ppi - finished size, in order to get a good quality image. (Be aware that the higher resolution, the larger the file size) Save the files as .tif or .jpg format and retain the high resolution for quality.
Adobe Illustrator / Freehand