Not understanding alt rows

Hi All! First-time poster here! I’ve been stalling on my latest sweater project because I don’t understand a direction in the neck shaping section. It reads like this:

Dec 1 st at neck edge on next 4 rows (I understand that part!), then on following 2 alt rows.

I am supposed to end up with a net decrease of 6 stitches. How many rows should I be knitting to do this? 8?

Thanks in advance!

Welcome!
Yes, you’ll be working 8 rows. Decrease on rows 1,2,3,4, 6 and 8. That’ll also dec 6sts.