Having my hair quite long at the moment, I usually keep it tied back. I buy the covered elastic bands, but to be honest, they're not too exciting, are they? I saw a way to cover them somewhere online (I can't remember the name of the site it was on, shout if anyone knows!), and this is my version of it.
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Take a covered elastic band, and crochet into it as when you're making a granny square; I use half trebles for this.
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Keep going until the circle is complete, and join to the first half treble/stitch with a slip stitch.
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For the next round, do two half trebles/chosen stitch into each space between previous stitches; continue around, and join as before. Fasten off and darn in ends.
The finished wrap, the double stitches giving a nice gently wavy edging.
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This is a good idea for using up little ends/scraps of gorgeous wool and yarn, not big enough for much else. You could make them to match a jumper just knitted too, with the leftovers. I want to try with other materials too - ribbon, narrow fabric strips, recycled sari yearn, cotton, etc.
Would make a lovely small present too, I think. The elastic bands can be picked up quite cheaply with cards of 10 or 20 available, in differing thicknesses and colours.
Much more interesting, to my mind:)