Silk is the traditional material that kumihimo is made with in Japan, in bundles of thin thread that are either prepared by the braider or purchased in pre-cut lengths. As silk is not always an economical choice, a product made from rayon or nylon called Imposter or Biron is also available. Imposter is generally sold in pre-cut lengths of four bundles of 105 inches/270cm each. If the bundles are folded in half you can make an 8 element braid of 17-25 inches/43-63cm depending on the structure used. While silk and Imposter/Biron is commonly used on marudai and other traditional braiding stands, it is less commonly used on the disk and plate, so I am sharing my tips for preparing Imposter for use so that you don't waste or ruin any of this material.
Gather your materials
You will need the disk or plate you will be braiding on, a spare disk or plate to act as a warping board, bobbins, scissors, a thin but sturdy cord such as C-Lon/S-Lon Tex 70/0.112mm/fine size, and your packet of Imposter.
Cut 12 pieces of your cord about 10-12 inches/25-30 cm long, and place to the side.
Remove your Imposter from the bag. One end of the bundle will be tied in an overhand knot with a relatively blunt end, the other will have a loop coming from the knot holding the ends together. The packet of Imposter will have the four bundles twisted around each other. At the end near the loop, separate those four bundles so they are distinct, and untie the looped knot.
Using the spare disk or plate, put the bundles into slots, with an empty slot between each bundle. Make sure the ends of the bundles are fairly even with each other. Untie the knot at the other end of the Imposter.
Working slowly to avoid tangling, pick up the long end of the bundle of Imposter in the first slot of your disk or plate. Trace it through and separate it from the rest of the packet. Once it is free of the packet, place the loose end in the empty slot next to the beginning end, leaving a tail that's about the same length as the beginning end. Leave the bundle on the disk or plate. Repeat this until all the bundles are separated.
Working with the first bundle, find the center point. In this picture it is loop in the center.
Take one of the cords you cut earlier and use a Lark's head or cow hitch knot to attach it to the center of the bundle. Repeat this for all four bundles.
Place the first bundle on the working disk or plate with the cord indicating the center in the center hole of the disk or plate. Do NOT yet remove it from the other disk or plate. Repeat with all four bundles.
On the ends of each bundle, attach another piece of cord using a lark's head knot.
Fold the end of the bundle around the knot so it won't slip off. Tie the two loose ends of the cord with an overhand knot.
Wrap the cord around a bobbin. Remove the end you are working with from the spare disk or plate, and continue to roll the bundle onto the bobbin, leaving about 2-3 inches of Imposter between the bottom of the disk and the bobbin.
When all the ends are removed from the spare disk or plate and the bobbins are wound, pass the ends of the cords marking the center to the back of the disk.
Cords sticking out of the back of the disk.
Tie those cords in a knot.
Hang your weight from that knot, and you are ready to begin braiding!
For more information on kumihimo silk bundles and Imposter, check out these articles at Braider's Hand: http://www.braidershand.com/tips.html and http://www.braidershand.com/threadsform1.html
Imposter can be purchased through Braider's Hand in the US/Canada; Carey Company in the UK/EU; and Braid & Bead Studio in Australia/NZ