Need help to choose the right keywords for my site content. I tried google trends and other tools, but I'm still lost.

Most search engines tend to ignore those keywords put into meta-tags, now - at least the bigger ones do.

They should exist within the content of the page, and NOT as a list of keywords or "hidden words".

Your going the wrong way I think it's the other way round you either have keywords and write them into content or your content is based around keywords as is your site.

Write what your going to write and try a tool like this to see if you've got it right.

http://www.keyworddensity.com/

If your looking for keywords then go to adwords and roll thrugh the subject to your own. The words getting the highest (not the most) bids are your keywords.

The keywords I insert into the meta tagging keywords of a webiste page are generally the words I see repeated at least twice in the content of the page. If some appear more than 5 times in a piece of writing less than say 500 words in length, I rather try think of synonyms to replace a few of those in the content (I edit the content) to avoid keyword stuffing. When I see there are rather important keywords repeated only twice, I further tweak the content to add them in once or twice more. Then I recheck and recheck again that the content still reads easily.

Only you know the right keywords IMO as you are the one running your website. I often check on my keywords and if they are not working change them. No one should keep their keywords the same year on year.

If it is a new site it is better to start with the less frequent keywords as well, and then move onto the best ones once you are well established in google.

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