Cable cast on 77 sts on a small circular needle. Knit Run out of yarn, change colour and knit some more. Repeat last step as you like. (K9, K2 tog) to end K next round (K8, K2 tog) to end K next round (K7, K2 tog) you get the idea? You need to change to double points, or do the magic loop thing along the way… until you get down to K2 tog to end, then break and gather up stitches tightly, weave in loose ends.