Welcome to Bitcointalk forum , you can join the sig camping in the service section (choose the one that accepts your rank) after being accepted in the camp you can go to your profile and edit your signature to the camp signature.
As a newbie you won't earn so much at the beginning so be patient , also there is a very good thread which is newbie friendly i recommend you to read it.
the link to the thread :
https://bitcointalk.org/index.php?topic=1244332.0Good Luck!