I assume you're asking how to post pictures. To do so, you need someplace to host the images. If you request it, you can get album space right here on this site (check the list to the left of your screen, and under "Navigation" you'll see "Photo Gallery").

Once you've uploaded a picture to a site to host it, copy the URL of just the picture. Then, under a topic or reply, you bracket that URL with the code <img>URL</img> (only the < and > are replaced with [ and ] ). Type in any explanation as you would a normal posting, hit submit, and voila! You have a picture in your posting.

The codes for images, underscores, italics, bold, etc. are also in a tool bar if you hit "New Topic" or "post reply".