Cut the cardboard in pieces of 25mm x 140 mm and put double-sided tape on them. Tape them on the GODMORGON unit.
We used 3 pieces taped together on one side of the GODMORGON and 2 on the other side. How many you need depends on the thickness of the cardboard you use. This is to make the tray fit better on top of the drawer and not fall through.
Just hang the GODMORGON small items organiser on top of your MALM drawer.