Most SEO experts teach you how to optimize a web page for good search engine ranking, but very few tell you what you must NOT do if you want to avoid over optimization penalty and see your page rank drop or your site get de-indexed.

Here are 10 things you should consider if you are serious about SEO:

1 - Website Content Theft:

Never steal content from other websites. If you are reported you will immediately be banned. Not to mention other legal issues.

2 - Standard Language:

Do not use slang or rude words in your copy as it can get you de-indexed.

3 - Outgoing Links:

Do not exceed 100 outgoing links, always link to good quality sites and never link to farm links. Extra tip: you must check your outgoing links on a regular basis to make sure they are still working and the quality of the sites you are linking to is still good.

4 - URL Length:

Keep your URLs less than 100 characters long and avoid using more than 3 hyphens "-" in your URLs.

5 - Keyword Density:

Keep your keyword density under 5% or it could be considered keyword spamming.

6 - Title Tag:

Your title tag should contain less than 60 characters and should not contain any special characters.

7 - Description Tag.

Keep your description meta tag under 200 characters or your site ranking will drop.

8 - Keyword Tag.

Put less than 10 keywords in your keyword meta tag and make sure every keyword appears in your web page copy. Also, avoid putting the same keyword twice in your keyword meta tag. The fact is that nowadays search engines (mainly Google) do not really consider the Keyword meta tag for ranking, but if you do not follow these simple rules, you will get smacked in the face!

9 - Proper use of Alt Text.

If you use pictures and put your keyword in the alt text, your alt text must describe the picture. You could write something like: "keyword header", "keyword image" or "keyword logo" but never stuff lots of keywords in your alt texts. Again, this would be considered keyword spamming.

10 - Cloaking.

Never, ever, use cloaking. Cloaking consists in coding the page in such a way that parts of the content will be seen by search engines but will not be displayed to users. If you do that, you will get banned!

Finally, remember that search engine algorithms change frequently. So keep up to date by browsing the SEO sites and forums.

These 10 simple rules are no guarantee that you will rank well in the search engines, however one thing is sure, if you break these rules you will be penalized in the search results, lose page rank and maybe even get de-indexed altogether.