1. Turn under the standard 3/8" and sew a long basting stitch. I use quilting thread for strength. Sew one segment counter-clockwise and end at the point of the heart, leaving a 2" tag (that will allow you to pull/gather later).
2. Sew the second segment clockwise, beginning again at the "V" of the heart.
4. Now you are ready for the "Secret Stitch" that gives the heart yoyo its unmistakable heart shape.
Knot your thread; Start stitch inside the heart, sticking the needle up through the top where the "V" of the heart should be. Make a tiny little stitch and pull down toward the gathered center. You can see in the Before and After photo better than I can explain it in words.
I tack that "Secret Stitch" to one of the gathers and then sew on my button.
I like to tack each stitch of the button to some of the gathers and then end by wrapping the thread around the base of the button and securing the thread. This helps the button stand up from the puffy gathers.