How to boost Quality Back Link in Google ?

Go for good social bookmarking, articles, forum sites to get quality back links.

It is very important.

The link should be "tough." Ie it is a written in html. There should only be done in javascript or in the form of redirection. Unlike hard links, links "soft" does not spread popularity.

Directory submission(Its the effective one way link exchange but it will take more time to show the result)
Article submission (
Social bookmarking
Forum posting
Press release
Profile sharing
Link exchange(Quality Outbound links only appreciated)

Referencing the site is important, but there is no way around it, Link Building is the most important factor in SEO.

signature links from forums is one of the best example of quality backlinks, a post on the forum become quality backlink when you do not spam on forums, plus a quality post is a good strategy.

forum posting, comment posting and most importantly, exchanging links with another site that is relevant to yours.

[COLOR=#000000]Exchanging links can be very helpful in your effort to increase your Google page rank. By simply endorsing other websites on your own site, you can generate back links that will help you enhance your Google reputation as well as drive traffic to your site.
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A backlink could be considered as a Quality Backlink if it links to your site with the keyword (keyphrase) that you are trying to optimize for and the theme for backlinking site is the same as website.There are a lot of technique to get quality backlink.