Go to staunton island go to the bridge connecting staunton island and shoreside whale put the cheat(L,up,left,R,triangle,circle,down,X and go very fast when u reach at the end press the button up u may be jump long and high, be sure u know the drive on water cheat (O,X,down,O,up,L,L)incase if u fall u may be succed trying a few timesby reachin the next bridge.
so best of luck!