Get maximum benefits from forum posting ?

As we are well known that forum posting is best way to get better traffic and grow up our site ranking .
Can anyone told me a new way to take benefits from posting ?

 

Join best forum site that have good pr . get their good backlink for your site

 

Post in the forum website with high pr...

 

Forum posting is best way of creating back link ..................

 

I think for getting maximum benefit from forum postings we have to post in the high pr forum site.