Tips/instructions for removing door panel

I have a 1989 Mercedes 190e and the rear passenger window fell out of the window track mechanism and is loose in the door.

Do I need any special tools to get the door panel off? Can anyone give me some tips/instructions on getting the door panel off so I can fix the window. I do not want to destroy the door panel to fix the window.

Any help would be greatly appreciated. Thanks in advance.

Dan