The Crochet Crowd has posted this wonderful Afghan Size Calculator! Learn how to figure out your starting crochet chain sizes for completing specific sizes of afghans. My formula with help you solve the math.
Double V-Stitch Edging.use this one to finish blanket. If using a different color than the main afghan for the border do a round of sc in the main afghan color before doing the border to get a neater finish.
This afghan is quick and easy, has built in borders and edging, and looks the same on both sides. After the first three rows, the same row is just repeated over and over, so a really easy pattern to learn.