or...

Get in a nice open space with atleast one tall strong tree. Place a picture of each car on opposite sides of the trunk one on the left one on the right. Now get 15 yards away and lower your head. Run full speed towards said tree until impact. Which ever side your limp body falls to is the car for you. If you fall straight back it means the Car Gods were not paying attention and you must sacrifise a virgin and try again.