1. Paging is better than scrolling. It is best to avoid particularly long pages as people often remember the location of an item on a page.
2. Use lowercase letters in preference to all uppercase because word shape is helpful in word recognition. (Don't write text in all capitals if you can avoid it!) (All capitals is also bad netiqette - it often signifies shouting.)
3. Monitor your line length - don't let lines expand to cover the entire width of the screen. Even if it looks ok on your screen, imagine what it would look like for users with widescreen monitors.  Line length in magazines and newspapers is kept short for physiological reasons - if a person has to turn their head, or use neck or face muscles to read a page, they don't take in as much information.  The same applies online - some sources say that the width of an A4 piece of paper (21.5cm) is optimal for on-screen reading. 
4. Divide your text into appropriate sections with clear titles as this makes it easier to scan (and it is good for increasing your ranking in the search engines).
5. Except for your homepage, (which often has to perform several functions), try to have no more than one motivator (focus) per page. If people have too many options to click on they often won't click on anything at all and will simply close your website.
6. Use emphasis sparingly. Emphasis on words (eg. a bold typeface or a bright colour) only works when it is different from everything else on the page and it is not competing with other strong features. If everything is emphasized, nothing will stand out.
7. Other considerations: if your target audience is likely to have less-than-perfect vision, you may also wish to consider the acuity of moving objects, contrast between the text and background, colour perception, peripheral vision and iconic memory when constructing your website.

Check how your website looks to people with different colour vision here: http://www.vischeck.com/vischeck/vischeckURL.php
Make sure that the contrast is high enough for people with visual impairments by using this website: http://www.accesskeys.org/tools/color-contrast.html

If you have anything you think should be added to this list, please contact us.