You will find that most polymer clay beads are pretty heavy, so be sure to purchase a durable material for stringing. A popular material used by many polymer clay crafters is Tigertail. This is a fine steel cable, covered with a plastic coating. Another material to use is Softflex, it is a little more flexible and drapes better.
Creating the beads is fairly simple, choose the style you would like and pierce the bead before firing. There are a variety of beads you can create, from circular to square to oblong, whatever design you would like. To pierce the bead, you will need a skewer or needle. Poke the needle almost all the way thorough, but do not allow it to come out the other side or you will create a lump around the edge of the pierced hole. Poke the needle through the other side as well. You can always fire the bead and then drill a small hole through the bead afterwards.
Fire your beads for about 15 to 20 minutes in the oven at 275 degrees. If your beads look brittle, you will want to make new ones so they don’t fall off the string.