Hi I think its confusable, Apply best technique of link building depend on particular that site. Analysis the site, analysis the competitors of site that after you decide the link building technique which is best.
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I can give preference as below 1. Social bookmarking 2. Blog commenting 3. Blog guest posting. If you choose high page rank website for this work you will get good search results.
Article submissions and blog posting have been my main focus recently but its also important to mix things up so I also do directory submissions, social bookmarking and blog commenting. If you can press releases are a good idea and also targeting your competitors backlinks.