To Avoid List
Avoid invisible text; that is, same or very similar text to the
background.
Avoid tiny texts that are hardly readable for a human.
Avoid irrelevant keywords. They render the other keywords ineffective.
Avoid excessive repetition of keywords. It may be considered as spam.
Avoid having different pages with the same keywords.
Avoid submitting too many pages in one day to the same engine.
Avoid submitting identical or nearly identical pages.
Avoid submitting to an inappropriate category.
Avoid frames. Engines don't like them. In case you need to use them,
don't forget to place the appropriate code in "<no frames>" tags.
Avoid pages created dynamically. Some times they disturb the spiders
work. In case that you use datafeeds, you may consider the possibility
to create static pages from your data.
Avoid links from your page to sites with questionable content. That may
be interpreted that you are in a bad neighborhood and cause you
troubles.
Avoid submitting your site when it’s unfinished. For example, with an
“Under Construction” page.
General Concept