Gear 5 is D.

So it is 1,2,3,4,D (5).

When left is D position, you can also "encourage" the transmission to shift up by tapping right, kind of like in some video games where even in auto mode you can still kinda shift. Not documented but works for me.

There is also the automatic downshift and you can use that by tapping and holding the stick left on deceleration, the tranny will shift to the most optimum gear for take-off once you hit the accelerator again, excellent for those corners.