Artwork must be supplied as an AI or EPS file (from Illustrator) or a PDF file (from Indesign). An EPS file is a vector file of a graphic, text or illustration. Because it is vector it can easily be resized to any size it needs to be and can be reopened and edited.
Ensure the Print Layer tick box is UNTICKED. The line must be coloured in a 100% SPOT magenta, yellow, or cyan (CMYK) depending on whether the artwork is full colour. For solid block colour(s) designs an outlined PDF for screen printing using Pantone (PMS) references is required - for example Navy blue pantone 289C.
Supply high-resolution minimum 180 dpi, maximum of 300 dpi. Large files may be emailed via a Dropbox or Hightail link.