You may have a site that is not getting target level visitors. In this situation you may take many steps to get target level visitors to you site. Your site may not be accurately optimized so you should follow some SEO tips to get enough visitor cause most of the traffic comes through search engines if search engine does not like your site then how could expect enough traffic. You may submit your site to many directories specially in DMOZ and to search engines. Your site have enough content that can enforce your visiters to turn back to your site and make then a regular visitor. You site should be updated frequently to get old visitor back.

Could you give a little more info like how to get your site optimized. Not how to tell if your site isn't optimized because that would seem pretty obvious.