You have to work for your on page optimization as well as off page optimization. As both the are of work is very importanat for the improvement of traffic of the website and regarding seo to get the best position in search engines.In on page -you have to optimize tittle,meta tag,description ,alt tag,site,header's, keywords. For off page optimization you have to work on social networking,social marketing,social bookmarking,commenting,article submitting,directory submissions etc.
These could be the basic action plan for your websites.Best Luck.