Debbie Bliss Cuff Booties

Hi! I am quite new to knitting and have almost come to the end of my first bootie-and now I’m stuck! The instructions are:
Cast off
With right side facing, rejoin yarn to rem sts and work as follows: K0 (1) [P1,K1] 7 times.
I have two questions-where should I be rejoining the yarn and also my row now has 28 stitches, but I’am only knitting 14 stitches!
Can anyone help? Thanks.

What part of the bootees are you knitting and what part have you just finished? I think this must be the picture for there bootees.