Help with pattern

Hi i’m Wondering if someone can help me with ‘translating’ a pattern?
I’m knitting a hooded cardigan Stylecraft pattern 9471 and to shape raglan armholes but cannot make head or tail of how to work this -
Shape Raglan Armholes
Keeping patt correct, cast off 2 sts at beg of next 2 rows. 47[49:53:55:59] sts.
Dec 1 st at each end of next and 1[1:1:1:0] foll 4th row, then on foll 13[14:15:16:19] alt rows. 17[17:19:19:19] Sets.

Can anyone explain how to work this out?

You will cast off 2 stitches at the beginning of the next 2 rows then decrease 1 stitch at each end of the next row, then work 3 rows and (depending on which size you are doing) either decrease 1 stitch or no stitches on the fourth row, then decrease 1 stitch at each end of every other row 13, 14, etc times (depending on which size you are knitting) until you end up with the number of stitches shown in the end brackets for the size that you are making.

I hope this makes sense!

Thanks so much for your reply and your help.