I start with a piece of backing fabric and a piece of a similar size batting. This time I spray basted them together, sometimes I just pin the layers (depending on the size). I then sew my leftover pieces and scraps into strips, about 4 inches shorter than the backing and as many as will fit.
After I've decide on the arrangement, I pin the first strip along one side of the prepared backing/batting, then line up the second strip on top, right sides together, pinning as well, and sew with a quarter inch seam along the side through all layers. Then I flip over the top strip and press it well. I continue with the next strip in the same manner until all the strips are sewn on. If you wish, you could now add borders (if there's enough space on the backing/batting).
After I've put the binding on, I decided it needed a bit more quilting since the strips on this quilt are quite wide.