If you would like to build links, then blog commenting is not very useful. Most of the bloggers has attached a nofollow tag to the comments and also the spam comments are immediately removed. Consider getting content based backlinks through article submission, blog posting, forum posting etc.
Social media is probably the most effective method for building links building especially bookmarking. I use a plugin for Mozilla Firefox although they have plugin for almost every internet browser but this plugin share every new blog article I write to every social media and bookmarking (stumbleupon, Pinterest, etc etc). Here's the plugin: Mozilla Firefox Google Chrome Internet Explorer Safari They are very excellent plugin and they are the easiest and is how I get several backlinks and main traffic as well. When you download the plugin for one of your internet browser and then go to the options on the plugin and add few of services I recommend: FaceBook (duh) Twitter (duh) Google+ Tumblr Reddit (duh) StumbleUpOn (you will probably get the most traffics and backlinks from this service) Digg Delicious Linkedin Diigo (When you sign up for Diigo, I would suggest you to look for some groups because that's where the backlinks and traffic comes from, so find some of groups that relates to whatever your website is about - If you need some assistance to learn how to use Diigo feel free to PM me and I'll teach you). FriendFeed (Almost same as Twitter and Diigo altogether. So when you sign up, join the groups/lists that relates to your website/blogs and when you post your website, articles or posts on FriendFeed you would need to mention all of groups that you have joined that relates to your website - Very useful like Diigo). Hope this helps you a little bit and if you need any help, pm me and I'll help you whenever it's possible.
Well, most of the link building methods now is cut down by the Google what left now is getting links from the forum signature panel, yahoo answers, try getting traffic from the Social media. What you can do is create a blog on your subdomain and start posting your article there share your blogpost over the social media network in this way your content goes viral and you will be able to get link juice out of it.
According to Matt Cutts We need to create Natural Links, google says your links looks Natural. Press release, Article submission are the best link building method, Make sure you have quality content.
Guest blogging is important, you can get quality of backlinks from there. You can contact bloggers offering you to write a quality post for them and simply you can leave back a link in that post. It will be do follow as well as it will be highly beneficial to rank your website. On the other hand you can also try forums for some quality links.
First avoid to do spamming. And do following link building techniques: Blog commenting Forum posting Directory submission article writing social bookmarking + ping state submission
avoid linkes from overSEOd blogs -- those, that, you know, accept any guest blog article, avoid traffic from suspicious sites with adult and pirate content, no matter what country they are from
What a great post! I have used their FireFox plugin in the past, but deleting it because it wasn't doing anything for me, obviously I wasn't using it as well as you were and I'm now giving it another try.