First pull the bonnet release which is in the drivers side foot well.
Next both these wire clips need to be unclipped and pushed towards the outside of the headlamp.
Then the back comes off the headlight, this is a bit fiddly to remove
Remove the back and put it somewhere safely.
Locate the tab in the back of the headlight that is part of the side light bulb holder, using two fingers GENTLY pull it out, it is very easy to break this tab off, you have been warned!
Bulb and bulb holder removed.
Replace the bulb, part number 10556890.
Check the bulb works before refitting in the headlamp, if you leave the light on it also makes it it easier to see what you are doing when replacing the bulb. It is important to make sure this bulb is fully home and does not rattle in its holder as this will cause the bulb to blow again in a very short period of time, a neatly cut piece of insulating tape wrapped round the bulb holder will help to stop any rattles but you dont need much and the bulb needs to be fully home or it will overheat. Now reverse the process above to refit the bulb.