Proofread all text for spelling, grammar and legibility. (A great trick for proofing spelling is to read it backwards!)

Print the document and stick it on the wall. Take two steps
back and make sure you can read all the key words.

Save print ready files at 300 dpi or even higher
to ensure the best resolution possible.

Ensure that all colors are in CMYK+OBG. Print the file and check whether you like it.

Check your crop marks, bleed and die-lines to see if all look aligned.