Excerpt from Web Style Guide: Basic Design Principles for Creating Web Sites, by Patrick J. Lynch and Sarah Horton.
Place yourself in the background
Start and end with the users’ interests in mind. If your site doesn’t provide useful things to the audience, nothing else matters. Design your web site with universal usability principles.
Work from a suitable design
Avoid the perils of the “ready, fire, aim” syndrome. The crucial part of the project is the planning. Know what you’re doing, why you’re doing it, and for whom you’re doing it before anyone touches HTML or Photoshop.
Do not overwrite
Small is good. A concise, high-quality site is much better than a big contraption full of broken links. Produce the minimum necessary to achieve an excellent result.
Prefer the standard to the offbeat
Web conventions are your friends. Always favor the tried and true, and save your creativity for the hard stuff: interesting content and features.
Be clear
Craft your page titles and content carefully, and make sure that the page title is consistent with your major headings.
Do the visuals last
Early visual design discussions can ruin any chance of a rational planning process. Louis Sullivan was right: form follows function.
Revise and rewrite
Design iteration in the early stages of the project is good. In planning, keep the team open to new ideas, feedback from existing and potential users, and the interests of your project stakeholders. However, development iteration—where you tear down and revise things late in the process—can ruin quality control, budgets, and schedules.
Be consistent
Consistency is the golden rule of interface design. Be consistent with the general conventions of the web, of your home institution if you have one, and within your site.
Do not affect a breezy manner
Avoid gimmicky technology fads. “We should use Ajax” is not a technology strategy, unless you know exactly why and how Ajax might benefit your site and help you achieve your strategic goals. Never use pointless Flash animations to “make the site more interesting.” To make your site more interesting, add substantive content or features.
Degrade gracefully
Apply universal usability principles in your site development and careful quality controls in your web applications. Provide a carefully designed “404” error page with helpful search and links if the user hits a broken link on your site.
Do not explain too much
Be concise, and be generous with headers, subheads, and lists, so the user can scan your content easily.
Make sure the user knows who is speaking
Good communication is always a person-to-person transaction. Use the active voice at all times, so the user knows who is speaking. Make it easy to find your mailing address and other contact information.