How to quickly add external links?
 

The fastest way there are two: First, spend money, and second, to write soft. External links quantity and quality of two sub-arguments, do not ignore the link quality.

I think used forum posting and blog comments.

Building back links too quickly is not a good practice as you get higher chance to be punished by search engines.

Here are some options:

-Social Bookmarking
-Social Networking
-Forum Commenting
-Blog Commenting
-Ezine article submission
-Web directory submission

Keep in mind also that quality of links is by far more important than their number. It is better to have 100 quality links from relevant websites than 1000 from farm sites, low quality directories or auto approve blogs!

Blog is very important. Google values more to blog than website that we all know. Blog must be update regularly.