The rightful person to do that is the person that introduced you to it, because they supposed to have hinted you about the forum already before bringing you into it, for you to already know how to create a post on threads, shows you have an idea but still having some challenges, well learning from other members is not a bad idea as well, my opinion is that you should first know the rules and regulations of the forum and abide to them so as not to make mistakes that would get you reported or banned, then as a newbie you should focus on easier topics that you would be comfortable to reply on, therefore giving reasonable and quality ideas.
 You're welcome to the forum, goodluck exploring and creating good topics that would fetch you Merits.