1- do onsite, offsite seo
2- list your site in directories
3- list your site in search engines
4- get links to your site
5- buy links
6- buy bannerss
7- join some affiliate marketing program
8- use email marketing
9- tell your friends, and ask them to tell their friends about their site
10- advertise where ever you can afford
11- asks for reviews
12- join forums
13- create newsletter
14- tell in chat rooms
15- get free stuff

promote, advertise, as much on directries, search engines, forums, blogs
hope that it would benfit you