Content
Don't make the ad about you or your product/service. Ads that speak directly to your target and share exactly why they should click on the ad (ie. what they stand to gain) perform best.
Try and piggypack on some existing ideal or habit
- selling cigarettes to women exploited the fact that women wanted to be emancipated. smoking cigarettes was linked to that
Favor content that will stick around in people's minds even after they have stopped looking
McDonald's had an ad showcasing the big Mac with bacon. Underneath, it said "with bacon, is it still a big Mac, or isn't it?"
- this is a good ad, because it causes you to think about it. What is it that makes a big Mac? Is it the makeup of the big Mac? Is it the sauce? The look?