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Slightly more than 2 50g balls of plain yarn (I had to join a 3rd ball just to do the last couple of rounds, annoyingly). I used a fairly chunky, slightly lumpy chenille type yarn.
1 ball contrasting yarn for stripes (I used a variegated self striping yarn).
6 mm crochet hook
3 buttons, approx 1 inch across
ABBREVIATIONS:
ch = chain
dc = double crochet
dc 2 tog = double crochet 2 together (decrease).
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In colour A, ch 54, join to make ring.
Rnd 1: ch 3 (counts as 1 dc), 1 dc in each chain (54 dc)
Rnd 2: ch 3 (counts as 1 dc), *ch 1, skip next dc, 1 dc in next 9 dc* twice, ch 1, skip next dc, 1 dc in next 27 dc, join in 3rd ch.
Rnd 3: ch 3, 1 dc in each dc (1 dc in each ch 1 space) (54 dc)
Rnd 4: Join colour B.
You don't have to fasten off with colour A - just bring the yarn up the inside of the rows, to join on each time you change colour (see below).
Ch 3, 1 dc in each dc (54 dc)
Rnd 5: Join colour A. Ch 3, 1 d in each dc (54 dc)
Rounds 6 - 22: continue as for Round 5, alternating between 2 rounds of colour A and 1 round of colour B.
Rnd 23: Join colour A. ch 3, dc 2 tog in next 2 dc, dc in next 22 dc, dc 2 tog in next 2 dc twice, dc in next 23 dc, dc 2 tog in next 2 dc, join.
Rnd 24: ch 3, dc 2 tog, dc in next 20 dc, dc 2 tog twice, dc in next 21 dc, dc 2 tog, join.
Rnd 25: Join colour B. ch 3, dc 2 tog twice, dc in next 14 dc, dc 2 tog 4 times, dc in next 15 dc, dc 2 tog twice, join.
Rnd 26: Join colour A. ch 3, dc 2 tog twice, dc in next 10 dc, dc 2 tog 4 times, dc n next 11 dc, dc 2 tog twice, join.
Rnd 27: ch 3, dc 2 tog, dc in next 10 dc, dc 2 tog twice, dc in next 11 dc, dc 2 tog, join.
Rnd 28: Join colour B. ch 3, 1 dc in next 25 dc, join.
Rnd 29: Join colour A. ch 3, 2 dc in next dc, 1 dc in next 12 dc, 2 dc in next dc, 1 dc in next 11 dc, join.
Rnd 30: ch 3, 1 dc in next dc, 2 dc in next dc, 1 dc in next 13 dc, 2 dc in next dc, 1 dc in next 11 dc, join.
Rnd 31: Join colour B. ch 3, 1 dc in next 2 dc, 2 dc in next dc, 1 dc in next 14 dc, 2 d in next dc, 1 dc in next 11 dc, join.
Rnd 32: Join colour A. ch 3, 1 dc in next 3 dc, 2 dc in next dc, 1 dc in next 15 dc, 2 dc in next dc, 1 dc in next 11 dc, join. Fasten off.
FINISHING OFF:
Sew in all loose ends of yarn. Lay cover flat and align buttonholes so they are evenly placed along the bottom. With a fabric marker, make a mark through the buttonholes onto the back side. Stitch the buttons on securely - if neccessary, use a small dot of glue to hold the knot in place. You won't need to block this - but be aware that if you use a wool or wool blend yarn, the heat of the hot water bottle will probably felt it a bit.