This article is especially for people who are trying to get the hang of SEO but do not really how how it works. First of all, SEO is an art and not a science. There is no secret of doing it right. If there were, people would exploit that secret technique to the point that it would be worthless, and we would be back to square one.
Even if SEO is not a science, we can tell from experience that some measures will simply kill your rankings or get your severely penalized. They are mentioned below:
1. Duplicate content on your website: If you have duplicate pages on your website, you are in a world of pain! Change your content so it does not match the other pages. Spiders leave your website when they see duplicate content so make sure that does not happen.
3. Filling your footer with junk: If you have loads of links in your footer connecting to junk websites or webpages, you will be penalized. Make sure you put only a few links in your footer.
4. Linking out to junk websites: You have no control on who links to you but who you like to is under your control. If search engines find that you are linking to a link farm, a bad neighborhood or a junk website, you are in lots of trouble.
5. Do not use cloaks or redirects: Remember, anything which is done to deliberately deceive search engines will be penalized if you are caught. Cloaking and redirects which deceive search engines are easily identifiable and should be avoided because they can get you banned for a long time.
6. Having server downtime: Try turning off your server for 3 days and Google will de-index you, which means that your website will not show up anywhere in the searches. If you have a bad hosting server, you will kill your rankings without even knowing it.
7. Keyword stuffing: If you stuff your keywords in your title tags, keyword tags and in the content to the point that you go overboard with it, you can expect Google to flag your website as spam. As soon as that happens, you will most likely get de-indexed.
8. Having little content: You need content to rank high most of the times. If you hve a one page website, it will be harder to rank high for it. If you have too little content, you might even get less weight from the search engines.