Writing effective Web Pages:
What not to do:
Print this and read it and you will find it is easier than reading it on the screen. Writing for the Web is not like writing on an 8.5 X 11" piece of paper. When you write on a piece of paper your eyes can scan down the discreet print format, jump to headings and paragraphs, turn pages, etc. The document is readily accessible, and our eyes have been trained and have adapted to paper as the medium. It is different for a computer screen's monitor. Small type is difficult to read because of the resolution of the type's display. Sentences fill the width of the monitor, and often are too wide. The writing style is differs. Browsers (you) on the web want to know immediately if the page is relevant to what they are looking for. For that reason, a "bottom down" approach is necessary, with the conclusion or summary at the top. This may seem like a superficial treatment of subject matter, and it can be. However, keep in mind that millions of websites compete to deliver information, and if your website is written in a clear, direct manner, you will succeed in delivering information.
Badly designed websites comes in several varieties: One of the worst is a page that is text heavy, which reads like "Moby Dick". Interminable text goes on and on demanding perseverance to get to the good parts. "Computer eyes" tire way before they get to this point. This is not to say that a page of heavy text is not appropriate for the web! Rather, the web can be a very effective way of delivering information that is printed, and then read. It is said that "reading" webpages is 25% slower than on paper.
Another variety of bad design is graphics heavy: extensive graphics not only take a long time to download, but can obscure your message. Often little ditsy graphics blinking and bouncing across the screen distract the reader. Banners (advertisements?) which have nothing to do with the content similarly overwhelm or obscure the message. Confusing images mislead the browser, confusing where to go in the website for more information, or leaving you in a limbo of irrelevant information. Often graphics take an inordinate time to download, and a long download time yields impatience. The end result: viewers move on.
Guide for understanding and design of Web pages (outside link)