1. Less (words) is (are) more. Audience attention is inversely proportional to duration of your message. Read up on your Strunk and White, then pare down your language, if you use any at all, to the bare minimum.
2. Start a conversation. Ask a question. Nothing hooks a reader like being asked for his or her opinion. Find a way to collect and exhibit the results, and you've gone from attention to engagement.
3. Use a single, compelling image. Look a the most compelling article layouts and ads in magazines. They will have a strong central figure, and a controlled level of detail.
4. Serialize. Look up Burma-Shave in the ad history books. Start something that can be extended over time. Use #7 below to build interest, and pay off your readers' gift of attention in ensuing messages.
5. Typography matters. Learn to design with type, and match the font to your message. For best examples, look at award-winning ads in trades like Communication Arts.
7. Mystery can be engaging. Don't give it all away.
8. Make it a masterpiece.
9. Surprise me. When all are shouting, whisper. Stand on your head. Paint your nose red. Attention goes to the unexpected, so think of the surroundings of your exhibit space, and make what's on the screen stand apart from that. If your exhibit is in Times Square, go B&W, or use white space.
10. Convey your brand respectfully. Stand on its shoulders, steal it's moxie, but don't ever mess with it. See Target for best practices here.