Agree. Article posting with proper keyword density ratio will be a great help. But one should not post same article in many article directories, this is what i follow. And apart from this there are many different techniques like, forum answer posting, blog commenting, etc.

Backlinks are formulating the PR but you should avoid looking for a particular PR as this has no meaning and is only one factor out of many. It would probably be best if you get backlinks from a wide diversity of sites, closely related.

dofollow forums, blogging are the key roles for the page rank.

you should do more quality content and quality links

Link is a very good choice that can gain page rank

To get good PR submit your website in high PR social bookmarking sites, do forum posting, article submission and blog commenting will also beneficial...

Use a combination of these to get a boost. Some will require more effort than others, so pay attention at how much time you have to spend to get your desired results.

Search Engines

If it's not obvious by now, just repeat out loud: This is the most important aspect of getting your site in front of people. A search engine uses automated programs to analyze web sites that are called spiders. You can choose which pages and page elements those spiders will see and record for their databases (more on that in an upcoming article). Currently the search engines that command the most traffic are Google, Bing and Yahoo.

Directories

Directories look and feel exactly like search engines except that they use humans to review sites and determine if and how they will be placed into their database. It can take a while for your site to appear on them, if it actually gets listed at all. It's best to just submit your site and info, then forget about it. Some higher-ranking directories charge you small fees for being placed, such as JoeAnt.com and GoGuides.org, but they will help drive traffic to your site.

Let me explain the right way to get high PR.

Submit comments or post articles or blogs in websites that have a good 'internal' page rank. It doesn't matter much if the domain has a high PR. What matters is the page where you post it. If that internal page has a PR of 6 or 7 then all your efforts are worth it because you will get better recognition from google.

Website content quality in on-page SEO and the effective strategies for posting methods in off-page SEO.
Then our website Page rank will improve.

For the use of linking like directory distribution, writing and submitting articles, report distribution, forum publishing with signature, blog comments etc.