1998 Audi A4

There are a couple of screws in the fender liner (some may behind the liner) that attach to the bumper.
Then you need to remove the two small grills on the front of the bumper. Behind those are two long bolts going straight up into the bumper brace.
There are clips on both side that hook onto the bumper. Spread them wide enough for the bracket that is on the bumper to be pulled free.
After all the bolts are out you'll need to gently remove the bumper skin and disconnect any wiring to the fog lights and the washer hose going to the headlight washers.