Kim Hargreaves Float Pattern Help

Hello! I’m a pretty new knitter attempting my first real clothing pattern. I just can’t seem to figure it out. Please help!

Work each side of neck separately (this part I get)
Working all neck decreases in same way as armhole decreases (and as set by last row), cont as follows:
Work 1 row.
Shape armhole
Cast off 3 stars at beg and dec 1 st at end of next row.
Work 1 row
Working all armhole decreases as set by back, dec 1 st at armhole edge of next and foll 4 alt rows, then on 4 foll 4th rows, then on 2 foll 6th rows and at the same time dec 1 st at neck edge of next and 18 alt rows, then on 0 foll 4th rows. 13 sts.

This is all Greek to me, please help!

Welcome to KH and to knitting!
If you call the cast off of 3 sts, row 1 then the following row is row 2 and the armhole decreases start at row 3.
Decrease at the armhole on rows 3, 5,7, 9 and 11. Then rows 15, 19, 23 and 27 and finally rows 33 and 39.
Decrease at the neck edge on rows 3,5,7,9,11, 13 and so on until you’ve decreased at the neck edge 19 times total.
These kind of directions can be confusing but mark off each row as you complete it and it’ll be easier.