You can appliqué one hexagon flower to a larger background square. If you have used the paper piecing method, remove the papers and press well with the iron to make sure the flower is laying flat. Fold the background into quarters and gently press in the fold marks to help position the flower in the center. Fold you hexagon flower in quarters and then match up the fold marks to get it centered.
Pin the hexagon to the background square. Use an invisible hand appliqué stitch and stitch the flower to the background OR after pinning in place, use a machine buttonhole stitch to attach the flower to the background.