As Shaun Crowley, a freelance copywriter and author of 100 Copywriting Tips for Designers and Other Freelance Artists, notes:
People often go online for quick, easy guidance. Headlines like How to…, 10 reasons why…, and 50 top tips for… promise the reader valuable tips, and they help you to highlight the key benefits.I also like Crowley's suggestions to...focus on the product's unique selling point...use a quote...start a story. All good advice that works just as well offline as on.
Also check out Human to Human Design, an article by Aussie web design consultant Sharon Lee, who says, "A good website is built on two basic truths -- that the internet is an interactive medium and that the end user is in fact human." It's always helpful to remember there are people on the other side of what you write.