I am making my a jumper and on the front, currently working on the neck divide and have come to these instructions:
Dec 1 st at neck edge of 2nd and foll 9 alt rows and at same time
inc 1 st at side seam edge of 4th and foll 8th row.
17 [20: 24] sts.
Please can you explain how this works because i dont understand how i am meant to reduce the number of stitches i have when i am increasing and decreasing by two