Since the dooms day clock is at the center of the world map, guess where you'll be trying to get to in the disorder. That's right, the center of the disorder. The route there isn't obvious, but the map LPChip mentioned will be a huge help.
The normal world map is a completely filled in square. If you haven't filled it in completely you should endeavor to do so. When you find a map painted on a background wall, take a screen shot. I know that's a horrible clue, but I'm sure you'll enjoy finding it on your own.