For this, you MUST be on the second island and NOT on the third one YET.
- Go to the heli tours (they should be on the bottom of the map that they provide you with on the second island.
- Steel the helicopter
- Ride the heli to the third island (then, you should get 6*'s)
- Ride around for 5 MINUETS then... WALAH
- 40G's for you