Your attention-grabbing headline can then be your biggest benefit, or a teaser to it. Make it intriguing, so it stops the reader, but don't make it unbelievable. It should feed nicely into the main body of your ad, where you can capitalize on the interest and arouse that desire. Pack in some benefits, and convey them to your reader in emotional words so that it really sizzles. Inject enthusiasm into your writing - it's infectious.
Flat adverts are a no no.
Create an air of mystery to ensure they are intrigued to click through. Be specific if you can, as it's far more believable. Once the desire has been aroused, motivate the reader to take action. Tell him to click through to your site, rather than just leaving your URL and expecting him to work it out. Give him an incentive to do it now, through the offer being time limited, limited product availability.