I'm fairly new to SEO and I have a site that was ranking #3 for its top keyword, now it has fallen to #15. What do I have to do to maintain my ranking? Any help would be appreciated.
If other people are busy building links and optimizing their sites then you need to do the same to keep ahead of them.
Bah the only problem with SEO is not to manage 1 site, 2 sites, 3 sites... its to manage 100 of them and update them regularly.
For maintain your site ranking and keyword positioning you should always in search of one way links and inserting fresh contents in the site. SEO work is not ends if u get position but difficult to maintain the position.
lots of promotion and submissions....yeah, link building / link exchanges to quality and related sites are very important.
Update update update. You don't have to do it everyday. I would try to schedule about once a week a new change to your site...kinda have to force yourself. This is something I neglect to do.