Merit is needed to rank up and it can be given by anyone who has it to give. As far as the quickest way to earn it, don't worry about trying to earn it. Just post normally and be helpful on the forum and participate in conversations where you are knowledgeable. Merit will come when it comes.
I am so much impressed with your words, it gives me motives and courage,I know it's not easy to earn merit as we newbie but we can't just be complaining on getting merits when we don't get to understand much more about this forum to gain knowledge about the forums, he's a newbie but he as earn much merits so far tho I don't know how good his posts are but merit don't matter I will also be happy if any of our senior high ranked members can give me merits ,but is just a matter of time merit will come when it's time we just keep making good posts I believe I will gain merits someday.