At what point can i add signatures
At any point. Navigate to your profile and change the settings in Forum Profile Information.
This is a link to that very page:
https://bitcointalk.org/index.php?action=profile;u=891453;sa=forumProfileNote that there are signature restrictions based on your rank.
- Newbie: No styling (including links) allowed. Max 50 characters.
- Jr. Member: Links allowed. Max 150 characters.
- Member: Unlimited length.
- Full: Color allowed.
- Sr. Member: Size allowed
- Hero: Background color allowed