Or it could be pieced with a 3" X 6" of the red and then a 2" X 3" strip of your scraps from your quilt and then a 3" X 6" strip of the blue fabric...keep alternating....
then you can lay the border strips around the quilt to find a way that looks pleasing to you, where the pieces will meet in the corners, and then trim the borders to length.
If you are going to piece the borders, a suggestion is to make the pieced sections not the same lengths as your blocks. That way it keeps with the scrappy look, and you will not have all of those intersections to match :wink: