When I have directions like this, I usually make a chart of which sides get decreases on which rows.
Arm edge - Neck edge
1d................1d
2d.................2
3d.................3
4...................4
5d..................5d
6...................6
7d..................7d
.....................8,9,10
......................11d
.......................12,13,14
.......................15d
.......................16,17,18
........................19d
.......................20,21,22,23,24
..........................25d
........................26,27,28,29,30
........................31d
........................37d
........................43d
It's late. I hope this makes sense.
