Begin your decreases at the armhole after this instruction:
" Continue to decrease one stich at Neck Edge, every other row, 3 times" (which I did)
If you call the first row after these decreases row 1, then you'll decrease at the armhole on rows 1,2,3,5,7,9,11,13. The decreases at the neck edge are on rows 4,8,12,16,20,24,28,32,36,40,44.
Chack off the rows as you do the decrease to make sure you do all of them and it'll all work out fine.