Sometimes I've been asked, "How much yarn do I need to do the long tail cast on?". Sometimes it is known as the two strand cast on. This technque is called the long tail because you begin by pulling out a long tail of wool. There are many methods, but I have always used both ends of a skein or two skeins. If you can find the beginning and end of a skein you can use the tails from the beginning and end to do your long tail cast on as you normally would. Just cut one of the tails and continue knitting as usual. Or if you cannot find the tails using one skein just use another skein and use the tails to cast on and cut one of the tails. This way you will always have enough yarn for that 400 st cast on.
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