Round 1: Work Single Crochet into each stitch around the blanket, working 3 SC into each corner space. Join the round ch 1 and turn.

Round 2: 1 SC, *SK next SC, 5 DC into next SC, SK next SC, 1 SC into next SC,* repeat *to the end. Join with a slip stitch to starting SC, tie off and weave in the ends. 

Skip to about the 14 minute mark to watch a video tutorial of the edge.