What you leave blank in a design is just as important as what you print. Elements that are close together communicate related ideas. Elements surrounded by space communicate emphasis or importance. Look at your design from 8 to 10 feet away. Symbols and print that are too close together will decrease readability.
Borders can help to highlight a design.
This means that it is black and white and clearly designed. Printers can reduce or enlarge the art to the correct size from this stage. Type can be set in one of hundreds of designs and sizes. Pick a few good fonts and stick with them. One or two for body text and one or two for headlines should suffice, although it depends on the publication.