Buttons are a good way to practise making small even canes of polymer clay. You don't need a huge cane to start, as you don't usually want a lot of buttons.
Begin the Cane Start a simple cane by rolling a center core from a tiny amount of a dark color of clay. High contrast canes work better for buttons as they are such a small finished object. Wrap this core with a 1/4 to 1/2 inch cylinder of translucent, white or pearl clay. Finally use a thin uniform layer of colored clay to wrap the white cylinder. This will form the base of your clay cane. Cut the ends off your short, thick, cane to make sure the clays are even throughout the cane.
