Export or save your files as PDF using the PRESS QUALITY or PDFx-1a preset from your layout program. Please make sure it includes a min. 0.125″ bleed, crop marks, Color mode CMYK.
If you don’t have the option to save it as PDF, you can save/export your file as TIFF or JPEG format, 300 dpi (Photoshop)-with min. 0.125″ bleed, CMYK.
If you can’t save your file as TIFF directly from the program that you created your file in, save your file as EPS then open your EPS file in Photoshop and save it as TIFF or JPEG format. Before saving your file as EPS, make sure all your fonts and placed images are linked correctly. All placed images should be 300dpi (high resolution). Convert all text/fonts to outline if you are using a vector application e.g. Corel Draw, Freehand and Adobe Illustrator.