After you image has been created to the above specs, post a reply to this message. Click on upload an attachment, pick the type of file you are uploading (gif or jpg) then hit upload file to server. Once the file has been uploaded you will see a series of numbers before the file extension. #########.jpg for example. Copy or write down this number and extension, you will need it in the next step. Once you have uploaded the file and got the name of the file (######.jpg), either close out this window or use your back button on your browser.
Go to the main menu for the message forum and click on the link "user menu". At the user menu click on "edit your profile". Scroll down to the Signature text box and place "http://www.softplansplash.org/dcforum/User_files/"; in that box, followed by your ########.jpg name that you just uploaded. It should look like this. "http://www.softplansplash.org/dcforum/User_files/#######.jpg";
DO NOT USE THE QUOTATION MARKS!!

Click on the "update" button at the bottom of your screen to update your profile.

OPTIONAL:
Once you have done this go back to the main "user menu" screen and click on "edit your preference". Scroll down to the bottom of the screen and click "yes" on "make signature editable for each post" and hit the "update" button. This will allow you to see the link everytime you post a message. The reason I suggest this step is that there may be a time that you do not want your signature to show up and you can just erase the signature link at the bottom of your new posting before hitting the upload message button (post) to send your message to the forum.

NOTE:
Do not put your signature link "http://www.softplansplash.org/dcforum/User_files/#####.jpg"; into the "Attachment" box on a new post. This will double paste your signature into your post.