You will need:
300g double knit, I used 5 colours of King Cole Limited edition double knit 100% recycled.
One 6mm crochet hook
Scissors
Darning needle

Terms used are American, Stitches used :
Single Crochet (sc), Half Double Crochet (hdc), Double Crochet (dc), Half Treble Crochet (htc), Treble Crochet (tc), 2 Treble Crochet Bobble, Slip Stitch (ss) chain (c)
Sizing
Each granny square is approximately 34cm length and width. If you wish to make a larger, I suggest adding one or two rows once you have changed from circle to square. If you want to make one smaller then omit outside rows of the circle. You can do the colour changes or use one colour/self striping yarn if preferred (not so many ends to tie in this way!)