Pretty straightforward. You need a T120 torx screwdriver. Unscrew the plastic panel on the door that covers the hinge, then you can lift the door free. Unscrew the metal hinge on the washing machine, then lift upwards and slide it off.
Sit the new hinge in place, attach with 2 screws (I had to use the original screws, because the new ones didn't fit), situate the door and hold in place while to attach the 4 screws holding the plastic front plate (this is the trickiest bit) and you're done.