I know this toy by the name of "knitting knobby". To use, get the knitter, yarn and a crochet hook or cable needle.
Thread the yarn down the center of the knitter until about 10 cm (just under 4") is visible. Wrap the yarn counter-clockwise around one of the spikes on the knitter (not too tightly). Turn the knitter counter-clockwise and repeat the counter-clockwise wrapping of the yarn on each spike. Next wrap the yarn counter-clockwise around the first spike and lift the bottom loop up and over the top loop off the spike so that it falls into the center of the knitter. Leave the remaining loop in place (it will be the bottom loop of the next round). Turn the knitter counter-clockwise and repeat the wrap and lift off of the bottom loop. Pull on the yarn in the center to tighten the work as needed - after a few rounds the weight will help with the tension on the final product. Continue around the knitter for as many rounds as needed to get a desired length of material. Cut the yarn to leave a 10 cm tail and thread the tail through the remaining loops to cast off. Then pull the end tight.
If you wrap the yarn too tightly you won't be able to lift it up and off the spike. An alternative method for the first round is to wrap the spikes twice counter-clockwise and lift the bottom yarn up and over the top loop into the center at each spike.
I hope this helps. Additional pictures and directions can be found with google. www.how-to-knit-guide.com/french-knitting.html
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