By 
One of the main factors in Google’s algorithm for calculating Page Rank (PR) and Top SERPs (Search Engine Result Pages) is getting quality inbound links from authority websites. Although the visible PR (in the Google search bar) is historical (it can be up to 4 months old), it is an indicator of the importance of that site in the eyes of Google.
PR – Google PageRank
Google PR uses a scale from 0 to 10 – there is a gray rating for dubious sites! A Page Rank of 10 is in your dreams! So 0 is the lowest and 10 is the highest. The scale is logarithmic, so getting a rank of 2 isn’t twice as difficult as getting a 1, but it is significantly higher!
So your goal is to get inbound links from high PR sites. Of course, the higher the PR of a site, the harder it is to get a link. But not always, more on that later!
Link Relevance
The next number is relevant! If your site is about Perfume, there’s little point in getting a link from a site about Washing Machines. If you get those kinds of inbound links, Google will smell a rat (pardon the pun). Instead, you should look for a site that deals with the topic of perfumes. Good PR links from such sites will make your ranking a power of good.
Keyword
And there is more: choice of keyword for the outgoing link. You’ve managed to find a site with good perfume PR and they’re happy to exchange links. Carefully choose a page that has content about the keyword (or phrase) you want to promote, and then request that the anchor text be that keyword (phrase). Next, which page should you link to on your site? You MUST have a page where the content revolves around the keyword you are promoting, ideally in the title, H1 and text content. So linking to this page makes sense to Google. Google is looking for natural hyperlinks that lead to pages related to the topic! Google will give you brownie points as a result.
One last point: make sure the webmaster you’re exchanging content links with doesn’t use the “nofollow” attribute on their external links. Links with the “nofollow” link will not pass Google PR to your site.
Well, you have all the information you need to maximize your Google PR 6 link usage. Of course, the key is to find sites with PR 6 or higher that exchange links. So here’s the crux of the matter and believe it or not, the tool for getting the best PR links is currently available for free. See the link in the resource box for more information!