Plymouth Pattern 1800

I am having difficulty with Plymouth Kudo Yarn Pattern 1800. It is a new cardigan pattern. I found that there was a error in the pattern which helped, however I am now on the third section of the pattern, the right slant diamonds, and picked up the 8 stitches along the salvage edge, but then it says to slip the last picked up stitch onto the left hand needle and purl 2 together. I only have one stitch, how can I purl 2 together. Can anyone help me?

After you pick up the 8 sts you should have 8 on the R needle. Slip the last one of them to the L needle and p2tog.