[Ruby707]

To improve page rank , there are some points such as

Guest post
Submitting website on different directories
commenting on other blogs
Regular updating
High quality content.

For improving Pr of the website/webpage, need of quality and quantity of backlinks because PR depends on it. And these quality backlinks will be achieved by good offpage activities including guest posting, others are local directory listing, relative forum posting, article submission, blogging etc. But for all activities unique, fresh and quality content would necessary.