You will need to remove the undertray
Undo the undertray fixings – beware the undertray is quite heavy
Carefully remove undertray
Do not forget to have a suitably sized receiving tray in place
With an oil catchment tray in position, use an 8mm Allen key or socket to carefully remove the sump plug. Fully drain the oil.
When the sump has emptied, wipe clean the sump plug area with a paper towel
Replace (new) sump plug and washer. Do not over tighten