You goals is to get to the checkpoint as fast as possible while going through challenging terrains, use nitro booster to get to the goal within the given time. Try not to crash other wise you will end up destroying the truck.
Use Arrow Keys to drive. Press N for nitro. Space bar to jump when rollover.
A context menu should be shown when right-clicking or, on touch devices, long-pressing in the game. This menu especially allows to play in full screen and control the volume.