This cast on is not only stretchy, it also creates a nicely chained edge. There are again many videos of it, this is the one by Knitfreedom is one of those I personally like best. One note – since the method really kicks in at the third “wrap”, I generally cast the first slipnot and work the first two stitches with scrap yarn, then start using the working yarn. In this way the cast on is all uniform.
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