Make It Scannable
Use appropriate headings, bold text, and lists to mark important information. The crew at 37 Signals execute this really well – and even explain how they test the effectiveness of this via their Signal vs. Noise blog.

Go Above The Fold
Put your best material “above the fold” – that is, within the top part of the page the user sees before scrolling downwards. It’s your best chance of getting your user’s attention.

Link Meaningfully
Instead of adding a link that says “click here“, use a descriptive one like Lance Armstrong’s Bike Shop. It improves the readability and the quality of search engine indexing for your site and the destination site.

Encourage Exploration
Explain your content as best you can with the limited space you have but provide links to related sites where more extensive information is available. This way, you won’t lose your users attention, and you’ll be noted as a source of valuable referrals.

Size Matters
Keep your paragraphs small, have one idea per paragraph and make sure the opening sentence outlines the idea. Large chunks of text deter the reader.

Introduce these rules into your online writing and see how you go.