Axis

In the frontal plane, AVL is -30, I is 0, II is 60, III is 120.
AVF is 90.
AVR is -150.

In the transverse plane,
V1 is 120
V2 is 90
V3 is 60
V4 is 30
V5 is 0
V6 is -30.

So, another way to think of it is to imagine it on paper in the way the ECG is written:
0 -150 120 30

60 -30 90 0

120 90 60 -30


If there is a superior axis, then you need to decide if it superior and leftward or superior and rightward. You do this by looking at AVL - if it is upright, then the axis is superior and leftward.