SEO s not about doing social bookmarking and article, SEO is how you optimize your On site , Off site and In site. Offering search engine a unique and new thing.

Link building is very effective SEO tool and it can help in increasing traffic for the site. You can get good quality link by proper implementation of proper on-page optimization and relevant keywords.

I focus on Blog Commenting, Directories Submission, Forum Posting, Social Bookmarking etc. But I can't see good result.

agree with @jeresteem99 very useful for off page.

There are many techniques which can be availed in order to increase the ranking of the site. Link building is a method which is used to get good back links for the site.

to be honest, I also do not know what viral widgets. By the way, the directory also helps to increase page rank by submitting RSS Is this true? People have tried before.

The off page optimization techniques of SEO are the best ways for link building.

Guest Posting
 

After panda Penguin updates, link building is more risky than it was in past. So you should search relevant website to your niche and post guest posts on them, you will get quality link from different domain, it will really help you to boost search engine rankings.

The best way of link building is off page optimization. With the help of off page optimization, you will get good quality links for your site, but you can enhance your results by on page optimization methods.

Off Page SEO assumes prime importance. It is necessary to concentrate on On-Page SEO too. It is possible to gain better ranking by making our website search engine friendly.

Qualitative content and focus of dofollow links are the best techniques of link building.

No doubt turn off page SEO is important, but we should also focus on the page sealift we will do our site SE friendly implement good page search engine optimization, it will be very easy to get the required key word ranking high.

It comprises diverse procedures to attain positive outcomes as outlined in this site. Link building has established to be tremendously helpful for us these days.

The link building campaign involves different procedures that can assist you in gaining positive outcomes. Keep in mind that the link building activity assumes true significance in modern days.

It's no secret Google uses links to measure the authority of web pages. If a web page attracts links from other pages Google's algorithm, the software it uses to rank pages and decide which page is number one for a search result, increases the importance of a page.