I suggest waiting a week or two. Get to know the forums, and learn how to post posts with some good content. A good way is one that helps other's or shares information that is useful.
But work on that for a week or two and then go into it. If you start and do bad post quality it ends up being a temp ban.
I have to re-support this opinion. You need to look around and see what you can get into and what conversations you can be included in before you jump into a signature campaign. Some campaigns require a minimum number of posts per week and some require it in certain topics. So do your research and learn the forums first. Good luck.