You can also gain ranking power by making outbound links from your site to other sites. The theory goes something like the following. You have a website for your gardening business and you want to rank for the phrase "gardening service San Diego." If you have an outbound link to other sites about gardening services and the anchor text of that outbound link is "gardening service", then that link can serve as a signpost to search engines that your site is about gardening services.

This technique has a potential disadvantage (there's disagreement within the SEO community about this point that remains unresolved): by linking to other sites, you are directing valuable PageRank away from your page to the page to which you are linking. So, you lose some PageRank, but gain ranking power for the keyword. You may not want to overdo it—maybe just a few outbound links on a few pages, and always to reputable websites. This is a technique that requires some finesse, so you might employ some testing to see where outbound linking can be most effective.