Someone asked me about how to fill the center if you cut the sections short. Look at the centers of these and you will see that I fussy cut some pieces from the fabrics to match the theme of each K
I make a yoyo and applique it into the center. If you use a blind stitch it will blend with no seams or thread showing.
Sometimes I just sew them in with my machine. Just make sure you overlap the yoyo over all the ends of your K center.