Quality links are links to your website from other sites with a competitive key phrase in the hyper link text, linked to different pages in your web site from sites with high search engine ranks.

most effective way is by implementing the fresh content and pay attention through OFF page SEO will lead you to bring quality backlinks.

Most effective way of link building is always try to generate back links on high PR and high authority websites. Link building can be done with the help of Off page SEO techniques.

any off page techniques. submitting your site to high page rank sites.

building backlinks with your relevant and highpage rank sites is actually effective way.

Forum posting, Quality Content and Press Release are the most effective way to gain backlink.

I Think all off-pages activities are essential.

1. Blog Commenting
2. Article Marketing
3. Press Releases
4. Social Bookmarking Sites

Using these five is where I would spend the majority of my time. Yes there are other methods, the methods of link building above are the most effective.

Hope this help you!!

Submit your website to high Pr sites by doing off page seo.

Niche Directory Submission, Forum Profile & posting, Blog commenting and classified postings are some good & effective techniques to build backlinks for a site.

You can follow the following effective way to building links :
A. Submitting to Website Directories.
B. Content Creation (Link Bait)
C. Social Networking & Building Relationships
D. Optimizing Your Social Media Presence
E. Submitting News Releases to Distribution Services
F. Guest Blogging (External Content)

I Think all off-pages activities is valuable for seo.