The basic "DONTS" for the search engines

• Do not use text that is the same or slightly different color as the background to 'hide' keywords.
• Do not repeat the keywords in the Meta tags (use them only once), and do not use keywords that are unrelated to the site's content.
• Do not create a title like "web hosting, web hosting, web hosting." This is considered spam.
•  Do not repeat the keyword to increase its frequency on a page (Keyword stuffing). Search engines now have the ability to detect this: they can spider a page and determine whether the frequency is above a "normal" level in proportion to the rest of the words in the document - this is also known as keyword density.
• Do not optimize a page for top ranking, and then swap another page in its place once a top ranking is achieved.
• Do not put misleading words on the page in the hopes of attracting visitors looking for another topic.
• Do not submit a page to the search engines that, once loaded, automatically redirects to a page of different information.
• Do not create a page that prohibits the user from using the browser's back button to return to the search engine results.
• Do not create "doorway pages."
• Do not submit the same page more than once on the same day to the same search engine.
• Do not put multiple instances of the Title Tag in the HTML code.
• Do not put pages of content in layers and position them off screen or practice the same kind of behavior by turning the visibility of the layers off.
• Do not use small or 'invisible text' in the page.
• Do not send query to a search engine with an automated 'rank reporting tool' hundreds of times per day.
• Do not purchase multiple domains and put duplicate copies of the web site on each domain.
• Do not participate in Link Farm programs.
• Do not submit different versions of the web site in the hope of getting multiple listings.
• Do not submit more than the allowed number of pages per engine per day or week. Each engine has a limit on how many pages one can manually submit to it using its online forms.
• Do not cloak.
• Do not support affiliate sites with the same or similar content but different site designs.
• Do not create a page that is stuffed with keyword content so far down the page that it is unlikely anyone will ever scroll down that far.
• Do not create a plain page specifically designed to rank highly, and then once indexed, upload a different page to your server.
• Do not put hundreds of 1x1 transparent .gif's on your page and assign them all the same ALT text. This is rather easy to detect.
• Do not use CSS to set the text size of a particular tag to 0% and then fill your page with 'invisible text.'