Posting in the forums helps a lot. You get gold for each post. Even though it's not a lot if you combine selling and a lot of the other things Erika told you, you'll add a lot more to you gold amount. It helped me, that's for sure.
However, post in the correct forum. Be sure to read each forum and subforum's rules. If you abuse the forums, you'll get banned. We don't want that, now do we?
Have fun!