Project a particular image. Projecting an image that is consistent with your business is important. Know your audience and give them what they want. Once you've established that your marketing pieces do the above, follow these elements of quality design. Understand how the reader looks at an ad.
Readers scan from left to right, top to bottom.
Imagine a Z on the page and be sure your copy follows the natural way in which we read things. Put your attention-getter at the top and pretend your headline is the only thing your reader sees. Place an additional attention-getter in the lower left corner, also known as the dead spot. In fact, this is a better place for your logo than at the top of the page where so many people place it. Use short and powerful active verbs.