SEO "Don'ts"

Keyword stuffing
Don't stuff a page with a keyword phrase. It's a turn-off for visitors and can lead to a penalty in the SE's.

The keyword phrase only has to dominate the page for the sophisticated analytical algorithms of the SE's to understand what the page is about.

Don't target too many keywords on the same page, it will confuse the search engines. If you want to target "blue widgets", "red widgets", and "green widgets", then write a separate page for each. In any case, you should target no more than three keyword phrases on a single page.

Flash and Graphics
Search engines can't read flash movies and pictures and any text content in them will not be able to be read by the search engines.

Don't over-use either, and be sure each page has enough text content to allow the SE's to decide what the page is about.

Hidden text
White text on a white background will be detected by the search engine itself, or by jealous a competitor who will report you for illegal, "black hat" SEO. Don't use hidden text because eventually your website could be banned from the SE's, and removed from their index.

Take a long-term view of your website, and don't be tempted to take short cuts or you could be removed from a search engine's index entirely. Such bans last from 4 weeks to a year depending on the search engine.

Dynamic urls and cookies
Use search engine friendly urls such as http://www.example.com/widgets/blue/product-1117.html

but don't use

http://www.example.com/index.php?cat=widgets;type=blue;productid=1117

If you have a website that is generated from a database, you will have probably to modify the code to make the urls more search engine friendly. Webmasters love setting cookies with information about their visitors such as country.

Search engines don't accept cookies, and they will be stuck at your home page. Ask your administrator to modify the website so that it recognises search engine visitors (robots) and allows them to crawl your site without cookies.