Conveys emotion - your print design should trigger an emotional response from your audience. That response might be to buy something, do something or tell a friend.
Has a simple layout - simple layouts make it easier to convey your message to the audience.
Uses clear copy - single lines of text or bullet points can make it easier for your audience to read the print content. Font size and typeface are also important factors to consider.
Highlights benefits - ultimately your audience wants to know how they will benefit from using your product or service. Your print content should effectively convey that message.