1. Hide text
Using the same colors, or low contrasting textcolors, hiding text behind images etcera, all these ways to put keywords in your pages without them being visible to your visitors are a definate nono. Google says me don’t like. And if Google says that, you’re out of the game.

2. Redirects and Multiple domainnames pointing to the same content
Redirecting is not a problem, if you’ve moved your content, put a 301 (permanent redirect) in place, and Google will transfer your ratings to the new place. The same goes for domainnames, if you have several domainnames that point to the same content, no problemo, just use the 301 redirect (or 302 redirect if it is a temporary redirect). However, it is recommended to forward no more than 5 different domainnames to the same site.
Frame forwarding (where you have an index.html file with a frame in it on the one domain, and this frame then loads a page somewhere else) and metadata forwards (where you say something like “This page has moved, please update your bookmarks and click here”, and then after 3 seconds or soe the page automatically reloads on the new address) are not done. Doing this will kill your ratings. And yes, really kill them, as in bang bang, I shot you down!

3. Duplicate content
Publishing duplicate content will not get you punished by Google. You are just punishing yourself with it! Duplicate content can be on your own site, as wel duplicated from other sites.
Ok, I see you frowning, some explanation: you content can be duplicated if you put the same text on different pages, or, if you have different urls pointing to the same content.

The most common example: http://www.icantinternet.org and http://icantinternet.org which give the same content, but are considered different urls by Google (yeah, I know). Solution, go to Google Webmaster Central, and set these two urls to point to the same (you can select your preferred url to use in Google).
As for the duplicate content from other sites, it’s easy, don’t do it. Don’t go around copy pasting other people’s content to your site. You may think it will help you, but it will only help these others, as they get rewarded for this by Google, and Google will not index your version of the duplicate content.

4. Affiliate content
Or content that you get from article directories. These offer no new content or value, and thus is useless. You could use it here and there inbetween as a filler, but it is best not to. Write your own content, or have it written for you, but make sure it is unique, fun to read and informative. Oh, and written for the readers, not the search engines. Search engines only index, they don’t like or dislike, you readers need to like reading your content.

5. Bad HTML
Being the webmaster, you need to make sure your html behaves. If not, bad html, must be punished!
Oops, sorry, writing style from another website (not ). But there’s a point in this, your the webmaster, make sure your html is well formatted, and according the standards. Google most probably doesn’t punish you for not following the standards (try running all PR4+ sites through the w3c checker, and have fun reading all the errors. You’ll know how to spend your evenings the next… 15 years or so). Don’t do it for Google, do it for the layout of your website, and do it for your readers.

6. Query strings in the URL
Google doesn’t get query strings. Google doesn’t like what it doesn’t get. There is something to say about that statement, I know. But the fact is, that query strings will not get you good grades. If you are using wordpress or some other package, use meaningful names, preferrably with the keywords for the page in the url. If you need to pass variables in the url, then try to connect the same pages as much as possible using the canonical link tag.

7. Keyword stuffing
Don’t go stuffing your title and first paragraph with your keywords. If you’re writing a page for a bakery, for the keyword bread, then do not start with “We sell bread, we have white bread, brown bread, corn bread, round bread, raisin bread, square bread, and other bread. Bread is what we sell.”. There are two reasons not to do this: First, your readers. They will see this, and not even try to read it. It’s obviously not intended for them, so they will leave your page. Second, for the search enginges. Search Engine Spiders are stupid, but smart as hell. They don’t mind that the majority of your site is unreadable (although, spiders are getting more and more intelligent, and they also start recognising well or non-well formed sentences), but they will count. And if they’re counting tells them that your keyword density is over 5%, they will know that this page is keywordstuffed, and not intended for your readers. Punished thy will be!

8. Duplicate Title and Meta Description tags
Face it, we all want to be different. Give your webpages the same privilege, let them be different. Give each one of them a different title, and a different description.

9. Keyword spamming
Don’t put keywords in your meta keyword or description tags that don’t appear in the page. Not always easy, since often you set your keywords and description meta tag fixed for the whole website or blog, and not every page is totally about those topics. But still… Give it a try.

10. JavaScript redirects and Other Cloaking
Showing your visitors something else than you are showing the Search Engine Spiders? Ouch… You think you can smart out the Google Brainiacs? Bad thinking. Better go flippin’ burgers, ’cause this song ain’t gonna last! Cloaking is an absolute nono. If Google catches you, your site is out of the rankings. Options? Flipping burgers, or buying a new domainname, and doing it right this time.

Et Voila, 10 SEO-things not to do. I hope you can all learn from them.
Say what? you’ve been bad? Really bad? You need to be punished? Ok, here’s an extra one, especially for you

11. Bogus Traffic
Don’t go out buying bogus traffic. You may think they won’t, but no worries, Google will definately see that your traffic suddenly increased from 25 visitors a day to 2000 a day. They will flag you, and it won’t be a nice flag! They will investigate, and if your traffic comes from the wrong places: punished, thy will be! (hey, you asked for it, right!).
No worries though. Google knows how StumbleUpon and the likes work. They won’t punish your for that.

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