You'll see that there is a slim "rib" on each side of the key. We are looking at the cuts along the length of this rib and no further. The first position is at the end furthest away from the tip. We'll read each cut from there toward the tip.
There are 8 cuts. Each cut has 3 possible angles or "depths" -- "1", "2" or "3".
1 = flat (no cut)
2 = mid angle
3 = full angle so that the cut almost touches the rib
Familiarize yourself with how each of these looks -- flat, mid angle or full angle. The full angle cut will often look a bit wider than the others.