What is the most important thing that your visitor is trying to do? Or, have your visitors told you about a problem that they have on your site? Describe the "scenario" that you would like us to review as specifically as you can. You don't need to list specific steps or pages (except the page you want us to start on). Describe the user's goals and the tasks he or she will want to accomplish..
Examples:
“I want users to be able to easily use the information on my site to plan a road trip around the Southwest. My scenario: Parents of 2 pre-teens want to take a road trip around Colorado and Utah. They want to start in Denver, stop at archaeology sites, go on hikes, and find nearby camping or hotels. They find my site by doing a search on Google for ‘visiting Anasazi ruins by car.’"
“I have an online jewelry store. We put our URL in our newspaper ads and most people get to us by typing the address. A shopper should be able to compare rings in a particular price range ($500 to $1000, for example), get answers to questions (can I pick the gemstone, for example), pick one, and buy it online.”