Shy.... If you have an image you'd like to post, you must first upload it to your own webspace that allows hotlinking. (AOL members can do this with the space they have on their account.) There are file storage servers that allow this, though most don't.
Anyway, once you have your image in hotlinkable space, simply click on the IMG button in the post and enter the URL. The image should then appear in your post when finished. If you do not have hotlinkable space, your only option is to post the link and let folks go to it.
Ann