Backlinks from Older websites will be more powerful. Usually the older sites are already in high page ranking place and also search engine bots give more important to all of its content. Do’s Submit your directory to high PR sites Submit article about your site and importance Join forums Join your site content related web sites and put your comments. Regularly update your content Be patience until your site get matured (at least 3 months from the creation date) Don’ts Submit too many directories Submit same article and content to many sites Participate the forums activities regularly. Just join and adding your site link into profile will not work as your expectation Backlink from non-related to your content also will not work better.