The quilt is just three blocks by four, with a border, then a (also border, and a final frame! This would measure about x Note that on the final right hand row of blocks you omit the furthest right vertical row. (The connecting row)
Great idea for a modular knit blanket. One simple shape makes a great quilt. Sidewalk Quilt by Pippa, an original design. Pattern available on her website and a similar version for sale in her Etsy shop.
Nine Patch Square Dance features nine patch quilt blocks layered with solid borders. I would use different colors for the strips though. Using strip sets helps obtain accurate measurements so all pieced Borders fit properly.