It is a very simple taks. Here's how to do it:
First you have to go to "User Control Panel" and then on the left side, among other settings & options, you will see "Edit Signature". Click it. And there you go.
Hmm, that's strange. From what I have read on the forum you can use a signature when your post count is more than 5 posts. And I see that you have already 8 posts . Click here for more info http://www.magle.dk/music-forums/563-signature-system-announcement.html. If it doesn't help then I'm sure one of the MIMF regulators will have it figured out if you only ask them