Creating a topic is easy.  Just make sure that you are in the appropriate sub-forum for the topic you wish to create.  Click the link "New Topic" toward the top and to the right.

1) Enter a Topic name (required - if you leave the subject blank, type a message and then submit, your message will not post and it will be gone.  The Back button won't help you.)
2) Select an icon to match your topic. (optional)
3) Type your topic.  
4) Select "Send your message".  Make sure you entered a topic name.

For more help, click the "Help" link at the top of the page.