Keep in mind that there are two separate counters now, Axis. Posts is easy to figure out. Your post number is equal to the number of "posts" you have. You post every time you make a new topic, or reply to a topic. Using the Personal Message system, or posting in forums where it specifies that your posts won't count (such as the High Roller's Lounge) will not count toward your post total.
Points, on the other hand, are sort of confusing. You earn points by posting, and when people reply to threads you start. You get 2 points per post you make, and 1 point for each reply made to a thread started by you. However, if the thread/post is crap and gets deleted by a mod, you lose points (I'm not sure how many).