A skein of yarn is a length of yarn that has been wound into a large coil or loop and then twisted and fastened together. Skeins are useful when washing, dyeing, and storing yarn, and a skein can be wound into a ball of yarn to use for crafts like crocheting and knitting. To skein yarn, you can use a chair, another person's hands, or tools such as a niddy noddy or skein winder. A niddy noddy consists of a long tube or dowel with shorter tubes or dowels attached at right-angles at either end, and to skein yarn the yarn is wrapped around this tool in a specific pattern. A skein winder consists of an upright wheel, usually with four spokes with yarn pegs at the ends, and it is used to skein yarn by spinning the wheel while the yarn is wound onto the yarn pegs.
The first step to skein yarn is to make a coil by winding the yarn. To make a good skein, it is important to wrap the yarn with an even tautness and to make sure it is not wound too loosely. It is common to skein yarn into loops made up of 100-400 yards (100-400 m) of yarn. The yarn can be wound using your own hand and elbow, the back of a chair, or another person's hands held some space apart.
To skein yarn using a skein winder, turn the wheel while guiding the yarn so it is held by the yarn pegs on each arm. On a niddy noddy, the yarn is wound in a specific way. First, wind it straight from one short dowel to the other short dowel on the same long side of the tool, then diagonally underneath the tool to the opposite side. The yarn is then pulled straight from short dowel to short dowel again, before being guided diagonally across the top of the tool. This pattern is repeated until you have enough yarn for a skein.
Once enough yarn has been wound, three short pieces of yarn are tied loosely around the loop of yarn. The beginning and end of the wound yarn is tied together before the loop is removed from what is holding it. Then the loop is stretched out between your thumbs and the yarn is twisted in one direction using one hand. To skein yarn properly, one end of the coil is then inserted into the opposite end. Once released, the yarn twists around itself creating a skein.