Upgrade all 4 festivals to level 5 and this will unlock all Exhibitions, PR stunts and Bucket List Challenges.
Off the bat, you will not be able to see exactly where each PR stunt is until you drive to that location.
A PR stunt is: Drift Zones, Speed Traps, Speed Zones and Danger Signs.
Simply get 1 star on each of these to unlock this achievement. Earning 1 star is fairly simple and most, if not all, of these PR Stunts can be beaten with very little effort, especially with a fast car.