You are already in the right place. You can earn 0.008 BTC per month for a Newbie rank if you join signature campaigns.

Here is the link https://bitcointalk.org/index.php?board=52.0 just choose signature campaign that you want and that accept newbie

Also,  to give you an idea when will you rank up, just see below

Newbie: 0 post
Jr. Member: 30 post
Member: 60 post
Full Memebr: 120 post
Sr. Member: 240 post
Hero: 480 post

Hope this inspires you to be active in posting.