The Main source of Increasing your site page rank is don't have useless pages or not found pages on your blog, check from broken links or images. Also provide useful content which is not found anywhere, Like write about your personal experience which is always ranked higher.
Page rank is dependent on the back links coming to your site. But PR shouldn't be your main focus. Like stated above, write high quality and original content. Google likes quality content and I've gotten numerous 1st page listings on Google with 0 back links and 0 PR just because I wrote a really good article. It's worth spending an hour or so to do research for an article.
Join forums. Submit your website to search engine directory. Link from related website. Create and publish article. Ezine ads or newsletters.
Pagerank is used to depends solely on number of backlinks pointing toward your website. However, I am not sure if the number of backlinks is only crucial factor to incrase PR or not. I have seen many websites got high PR without high PR or quality backlinks pointing toward them while some website which has a ton of backlinks got lower PR somehow.
Submit your site to high PR Dofollow Social Bookmarking sites and Directories that helps increase ur PR
Most social sites give a profile page to their members where one can put a link. If link aren't clickable it is still worth to put a link, hard links do have a value. site like, digg, mixx, stumbleupon, tweetrl and may social bookmarking and social media sites
Don’t be obsessed with PageRank. It is just one isty bitsy part of the ranking algorithm. A site with lower PR can actually outrank one with a higher PR. Read more: http://www.searchenginejournal.com/55-quick-seo-tips-even-your-mother-would-love/6760/#ixzz0wC5R4pOm
Why is the reason you believe you need to increase your PR is it because you are trying to rank higher in serps? if so I wouldn't worry too much about PR just keep building quality links you should start moving up serps.
Why you guys crazy about page rank? just start driving traffic to your site with quality back links, google will give you good rank.
PR depends on both the quality and quantity of your backlinks. It seems that Google hasn't updated pr in large scale for quite some time.