The following post was inspired by 10 Usability Principles to guide you through the Web Design Maze http://www.humanfactors.com/downloads/10tips.asp
To motivate your users you must first understand their personae. Then you need to design your site to meet specific their needs and goals.
2. User task flow
Understanding your users, who they are and what they are trying to do. For your site to be usable, the website's flow must match the user's workflow.
3. Architecture it's 80% of usability
Your site needs to be easy to navigate, and not just for you and your team. Use card sorting and other classification systems with groups of your target users.
4. Affordance means obvious
Make links look like links, buttons look like buttons, and banners look like banners.
Save design time, and the time is take users to learn your navigation scheme by using templates.
6. Usability test along the way
Test your ideas early and often. Use paper prototypes first, followed by wire frames…
7. Know the technology limitations
Where ever possible keep it simple. Try not to use technologies that may alienate some of your customers.
8. Know user tolerances
Don't waste their time. Design for a 2-10 second maximum download. Reuse header graphics so they can load from cache. Avoid excessive vertical scrolling, and avoid horizontal scrolling all together (800 pixels wide).
9. Multimedia be discriminating
Think carefully about why you are adding animation to your website. Animation attracts attention to specific information. Too much movement distracts, slowing reading and comprehension.
10. Use a stats package
Track visitors through your site so that you can fix the pages that don't hold the users interest or that they can't find.