You are not going to rank well on the major search engines for
every potential keyword in your industry. There are millions of sites
on the web all competing for quality search rankings. So, with
keyword optimization, it is better to focus on quality as opposed to
quanity.
You need to select a few key words which you think you can rank well in. These are the keywords that
you are going to go for. Throughout your webpages, you should reference
these keywords so that your pages have a good keyword density in regards to
these keywords. Moreover, when other sites link to you, you should
have the anchor text be these keywords to greater your positioning for this
key word. You need to make these few keywords a focus of both your site
content and your link backs. Also, your title and meta tags should focus on
these keywords as well.
By going for a few keywords, you will give yourself a shot at getting good rankings. On the
other hand, if you go for hundreds of key words, you may not get quality rankings for any of them.