1) 0.125" total bleed all around (0.0625" for each side) is required.

2) File must be cmyk.

3) Images should be 300dpi.

4 ) Embed or outline all fonts.

5 ) Embed all images.

6 ) Make high res PDF from your file.

7 ) Files for multiple page products should be prepared as one PDF file with multiple pages. (example: 2 side postcard should be 1 PDF file containing 2 pages)