I'm guessing this will be the same for any car but I didn't find anything approaching simple instructions or with photos, and it took me a fair bit of head scratching before it all made sense.
you will need:
new gas struts
flat blade screwdriver- small
a prop
at each end of the strut is a plastic nut, around which you'll find a metal clip that acts as a locking mechanism.
Prise off the metal clip with a flat blade screwdriver.
Use a broom handle or similar to prop the hatch open. If you don't, when you remove the struts it'll drop on your head. I used a mop handle and jammed it between a heavy box in the boot and the interior grab handle so it wouldn't slip, and pulled the hatch down a bit so it was jammed pretty tight before I started.
Pull the strut nut away from the metal bolt, you might need to wobble it a bit but it'll come off easily.
Push the new strut back on, bottom end first. You might need to twist it around to fit both ends. Repeat for the other side
photos attached
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