Temari are constructed from the center outwards. At the core you need something to form the basic round shape. Some people use a styrofoam ball since it's already round, however this isn't for me; I like to start from scratch. Instead I use rice hulls, which are used in beer and wine making as filtering material. I take part of a new, clean sock or stocking and fill it with rice hulls — the amount depends on the size I want for the final temari. The bell box is nestled in the center of the rice hulls, and the top of the sock or stocking is folded over. The next step is to form it — almost like a snowball — into as round a sphere as possible, and then wrap with yarn. I'll save that for part three.
Alternatives to rice hulls (which are traditional in Japan) are scraps of fabric, cotton or bamboo batting, even the left over scraps of embroidery thread that are saved when sewing the pattern on the temari. Dried lavender or other scented flowers or flower buds can be mixed with the rice hulls. Or catnip, should your cat be a temari connoisseur!