
Off page Optimization is one of the method and technique in search engine optimization which work off the Page, like getting relevant links from other sites, link exchange with quality relevant sites, choosing etc.,
Off Page Optimization Techniques: 
Link popularity building:
Links play key role to driving traffic from all Search Engines. A quality back link is helps to develop a unique traffic and ranking for all keywords in Search Engine Ranking for which you do link exchange.
The importance of link popularity varies with each search engine, but every link to your web site is an endorsement of your site's quality, and increasing the visibility  of your site. We vary your link text and replace it with related  keywords to ensure maximum results for your site. Link building  technique is not only to increases your rankings with the entire major search engines but also brings targeted traffic to your site.
Types of Link Building: 
One Way Link Building 
Reciprocal Link Building 
Buying a Links 
One way linking:
Exchange a link with other website.
Most Search Engines like Google, yahoo and Msn give more value and weight on a site’s link popularity.  If your website is visited by the users then its count as quality  website, then you will automatically receive random linking to your site  with little work on your part.
Two  ways to increase your chances of one way linking is to provide quality  content for your site and the other one is to get your site listed in  the major human edited directories. Currently the two most important  human edited directories are Yahoo and the Open Directory Project  (www.dmoz.org).
Reciprocal Link building:
Reciprocal linking or two way linking is where you provide a return link to the other Web site in return for a link to yours, which is less valuable than one way direct links.
This  type of linking is done when it is difficult to get one way links. Many  search engines use a search algorithm which analyzes the quality of the  site linking to you.
Buying text link advertisements:
This  is one of the more expensive options in a link building campaign and  black list by search engines. Text link advertisements are bought from  relevant sites to increase link popularity of the site. Buying a link is also the quickest method to give a quick boost to your site’s rankings. While buying the links, the main criterion is Page Rank. Linking with pages having a high Page Rank is the only way to give a quick boost to your site’s rankings and drastically improve targeted traffic.
Buying a link from high page rank is bad seo technique and it should be adopted for only six to eight months (short term strategy) and help to boost PageRank of your website will get from such a link, you will find it much easier to find other high quality free reciprocal link partners.