Make it obvious – The Web application screen should clearly present what it is about. As far as possible it should be self evident. The browser title, page title, section headers etc. should make it obvious what the page is about. Also things that can be clicked should be immediately identifiable as clickable and shouldn’t require any thinking from the user.
Create a clear visual hierarchy – Newspapers have been using visual hierarchy for a long time. The hot news of the day always appears as the biggest text. The same should apply for Web page design. For example, the page title should be more prominent than anything below it. Also content relationships can be explained visually using hierarchy. GUI controls such as tab panes can be used for this.
Follow conventions – Unless you are creating a design portfolio or a flashy demonstration, your Web site should follow common Web page conventions. People think that underlined text is a link, a button is clickable and bigger text are headings. Keeping the text readable and non cluttered is very important.
Avoid needless text – If you have a button with text "Login", you don’t need a help text above it saying that "click Login button below to login to the system". It is stupid and redundant and it only adds unnecessary noise to the screen. Help text is rarely required and even if it is needed, it should be hidden by default. A web user needs help text only once!
Provide proper navigation – Web application usually doesn’t give any sense of scale or direction. As a user we have no clue as to how many pages are in the system and what options are available. The purpose of navigation is to help the user in navigating through the relevant pages with minimal thinking effort.