Getting links through forums is the most easiest way and it should be done only in decent forums which have a good PR to get the desired benefits. You can also buy one way links from various websites who offer this facility. Prices of the paid links will depend on its page rank and the popularity of the site.
May I ask, how to use social bookmarking to drive traffic to your site.
I join several bookmarking but the traffic still low.
How the social bookmarking works to drive traffic?
First you should enroll yourself only in top social networking sites, be a active member and should be a known entity. Once you are actively participating in the site you will attract traffic towards your site. If you have a blog you should also post your blog articles in there to get maximum benefits for the site.
just find a way to somehow make it worth someones while to link to you, sort of how some directories require a recip link in order for your site to be listed
Consider avoiding sites that openly sell inks.
If you get inbound links from sites that sell links openly, you are going to get slapped hard by Google.
1) Directory Submission
2) Articles Submission
3) Common link exchange with relevant sites.
4) Forum posting
5) Social Bookmarking
6) Blog posting
7) Sponsoring Free templates.
8) DMOZ listing. Because many directories get their data from DMOZ.
9) RSS Feeds that other people can use to show as news or resources on their site.
10) Press releases.
Most effective one is social bookmarking. But the only problem with this is -- link stay there for 3-4 months only. After regular interval of time you need to submit again.
The returns are much more than your time investment ( or money if you hire someone).
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