[suzeeq]

Okay, just CO a stitch number that's divisible by 4 (like 88 or 92) and k2 p2 for 4". The extra 2 in the original are for the seam and you won't need them.

Then I would do the odd rows as the WS rows in reverse, but that would basically amount to the same thing as written - k1 p1. Do the even rows as written however the decrease rows need to be adjusted because you don't have 90 sts to begin with. 88 would work better, so row 4 will be k9, k2tog, row 6 will be k8, k2tog and so on - just knit 1 less st between the k2togs.

That should be all you need to do really.