Okay, it's worded funny, but I think I figured it out....
Small: Work 1 round St st. Repeat this pattern 5 times, for a total of 25 rows: [K 4 rounds, K 5th round until second to last stitch before marker, M1, K last 2 stitches]
Medium: Same as for small, but on last round of last pattern repeat, M1, K1, M1, K last stitch. (instead of only making 1 stitch)
For the medium you k4 rounds, then increase 1 st on the 5th. Do that for a total of 25 rounds, except on the 25th round, you increase 2 stitches. You started out with 30, plus 6 stitches increased (1st on 4 rounds, 2 sts on the last one) equals 36. I think you increased 2 stitches in all rounds which got you 4 extra stitches.