Well you just started one... - Just kidding, I moved your post into a new thread because in that other thread it was off-topic.
Well the first thing is to choose the forum section you want to post in, then click the blue "New Thread" button at the top, left handside. In the next screen you can choose a thread title (that's a story in itself - we encourage people to come up with clear and informative thread titles instead of "Please help!! Having problems!!").
That's it! Pretty simple.
You might already be experienced as far as the forum structure is concerned. Typically new members would post in the wrong section sometimes - the posts would then get moved by the admins/moderators.