Hi Jerry,
The picture you want to post must reside on a Web server. The bulletin board does not have the ability to store a picture for you--it just points to a picture that is already hosted somewhere in the Internet.
Often, Internet service providers offer 10MB or more of space on their Web server where you can post pictures or Web pages, so you might check into that.
Once your picture is hosted somewhere on the Web, compose a bulletin board post and click the "image" button located below the box where you type in your message. Enter the URL for the location of the picture and you're all set.
Regards,
Chris