As rms mentions, most of SEO is basic practice and are things you should be doing anyway. If you want your site to rank better simply provide something people

As rms mentions, most of SEO is basic practice and are things you should be doing anyway. If you want your site to rank better simply provide something people want and try to give good, fresh, content on a regular basis. This is perhaps the best way to achieve a good (organic) ranking. Users you "earn" also tend to stay longer, be more active, more loyal, and will link to you and spread the word anyway, which is what you want. With good users and traffic you will automatically get better rankings and have good monetisation options too, such as advertising/adwords, if you do not already charge for your service. Lastly, have a blog as that is probably the best SEO tip most sites do not utilise.