A contest that is engaging, that piques customer interest and demands interaction, will make your site hot-list memorable. Also, there are a number of sites dedicated to listing links to stores holding contests and 'freebie' offers, so register your promotions with these sites. Then follow through by issuing a press release. And by posting your privacy policy, you can assure customers that any contest you offer is not just simply an excuse to accumulate personal data. Next, contests and freebies provide incentive.
Many retail websites offer no discernible impetus for a customer to act.
Product offers are often articulated in drab, neutral tones that almost seem to resist closure. Provide an impulse for action, but don't push. For service oriented sites, consider offering a limited or introductory service for free. If clients find your service indispensable, this marketing vehicle may be your sharpest. Also, there are many things you can offer for free unconditionally .