You want to cut horizontal sections from the t-shirt and tug on them. I found that as a general rule, the thinner the section, the longer the layer was when tugged on. I did thick and thin pieces for a more layered look.
You should have something looking like this. You want to arrange now in the order you like. I put all my seams together and placed the longer ringlets to the back.
You then want to cut a thin section from the t-shirt and wrap it around the backing. Sew this shut towards the inside of the necklace. You could use fabric glue also. Make it nice and tight.
Cut a thicker section to go on the necklace. It should be thick enough to hold the buttons of your choice. Try it in the mirror, then sew this towards the back of the necklace, pulling the thread through some of the rings to ensure it stays put and doesn't slide us and down. Wrap it tight too. Once again, fabric glue is an option.
Sew or glue on the buttons in a way you like. I put the butterfly in the middle and accented it with some shiny blue buttons. To make it look more jewel like, i avoid buttons with the holes all the way through.
Thats it! Try it on! =)