Firstly remove the 4 TX15 screws holding the aluminium door-lock trim plate. The two short screws are in the bottom, the long ones in the top: -

Remove the trim plate.

Remove the door sill plastic trim (it just pulls upward) and pull down the door rubber to expose the clip at the bottom of the trim, remove the clip carefully.

Open the rear stowage compartment and pull of the trim plate below it - it is hooked in at the bottom so pull the top outwards first. Here is a picture of that trim removed, the hooks hook into the bottom of the stowage compartment: -

This exposes a single TX25 screw holding the side panel which you should remove.

The screw is shown on the right of this picture: -

The side panel is clipped into the side of the car with two clips, and hooked into the rear trim section. Pull the panel of the clips at the side gently and slide it toward you to remove it, unhooking it (downward) from the top of the back section.

When re-assembling, if the 2 clips are damaged at all, please replace them - part number A011 988 46 78. Also remember to hook the top rear hook in first and the push the clip below into the back section properly.