You will need:

• 60g 2-ply soft cotton yarn, my favourite is Clea1000 by Circulo Yarns,
• four flat plastic (or wooden) rings, one inch outside diameter, 0.5 inch inside diameter (different sizes will work too, but consider they need to fit nicely on your foot)
• crochet hook 1.75mm, 1.5mm,
• darning needle