in a nutshell:
Open bonnet, 4 rivets along the top, push through/screw into and pull out the centres, then lift them up with flat screwdriver and pull out
screw and clip at each side of the arch liner holding the sides into place, unscrew
Underneath screws connecting the undertray to bumper(2 i think, if you still have one)
pull the bumper off, dont be afraid to manhandle it a bit it can take a bit of abuse - same goes for when you're putting it back on
and watch for you foglight/washer jet connections.
I thought i had seen a guide floating about on here a while ago