The pattern wants to increase 14 sts on the next row so that you'll have 84 sts total. The cable cast on is one of a few ways to increase many sts at once. So, what you have to do next is; * At the beginning of the next row, insert needle in to the space between the first and the second stitch and knit as usual. Place the new st just knitted on to the left needle. Repeat from * until you gain 14 cast on sts.