I guess you can earn your first merit thorugh this topic (the easiest way) --> [Merit] Hey Newbies! Can You Sign A Message?

As mentioned by mk4 you need at least 10 merits and 60 activity to become a member, read this faq about merit, ranks and activity - FAQ: Everything you need to know about forum 'activity, account ranks and merit

Note: don't ever attempt to beg for merits