Programs: Adobe Illustrator and Adobe Photoshop.
Files: Illustrator (.ai); Photoshop (.psd); Photo File (.jpg); Encapsulated Post Script (.eps); Portable Document Format (.pdf).
Resolution: 300+ dpi.
Art size: Size the artwork as large as you'd want it printed on your tee.
Misc: All artwork must be computer generated (it can be done by hand, but needs to be scanned in) and saved as one of the files above. Using fonts? Make sure to save as a .pdf or .jpg as we may not have the same fonts as you do. Images from the internet will not screen print well, so just don't use them!