There are several methods to increase traffic such as Article submission,Social networking,Affiliate marketing etc..
They play a vital role in improving traffic.But these all will take little time .
If you want to increase your page rank even more faster,paid SEO service is the best one.
I used the SEV(Search Engine Visibility) service available in Thewebpole.com
It will promote your site by submitting it in 100 search engines,directories and provide suggested keywords.Hence the website and page rank increases soon.