"Round 11: * K1, p1, (k1, p1) in next st; repeat from *
around – 72 sts."
The (k1, p1) in next stitch is your increase.
On this stitch knit it as usual, BUT DO NOT take the old stitch off the left hand needle. Instead leave it there, and after you make the knit stitch make a purl stitch through the same loop. THEN tak ethe loop off of your left hand needle. You have now made two stitches out of one.
The entire row between the ** gets repeated so
K1, P1, (k1, p1) in next stitch, K1, P1, (k1, p1) in next stitch...to the end of the row. This should get you to 72 sts.