I drew a line diagonally up the middle and stitched 1/4" each side of it, then cut them apart. I now had squares that were two different prints each. Then I sewed them together to make a quilt. I've attached a photo of it - it's a baby quilt but could be done in any size.
Also pre-cut squares would make nice pinwheels. Lay 2 squares together rights sides facing one another. Stitch 1/4" all around the four sides. Then cut an X in the squares from one corner to the other diagonally both ways. You will have 4 triangles. When you open them play with them until you get a pinwheel! Easy block and make a nice quilt. I've also attache a photo of a baby quilt I made with pinwheels.
Hope this helps!