I am knitting a pair of socks and have done ok until I reach the instruction of the heel flap. This sock is done on three dpns. The directions state-Heel flap: k1 st from end of N2 onto N1, k across 19 stitches on N2 and across 13 stitches from N3 for a total of 32 heel stitches. Turn work. Then there are 4 rounds of various stitches which I understand. I just don't understand the heel flap thing. Am I slipping a stitch from the end of N2 to N1 or am I knitting across N1 until I get to N2 or am I...

Thank you for any assistance. This has been one hum-dinger of a sock pattern. I keep messing up.