Open the bonnet. Release that catch that is above the grey box behind the headlight module. Then unplug the wiring loom from the light bulb. Then, undo the metal holder, if you get a mirror wiring looms
in there first you'll see what it is I mean. Remove bulb, replace it, making sure that the little nobbly bits on the bulb fit in. Its form a triangle, It's hard to explain but once you see with a mirror what is what, you'll understand. Try the drivers side first, if the passenger side has gone, you'll need the practice because of battery holder being in the way.