You will needA black chunky, relatively loosely knitted jumper
A 4mm crochet hook
About 4 large balls (pfffffff - mustn't giggle!) of indigo wool - mine cost £1.69 each from Hobbycraft
Gold felt pen for marking out your design
Copious patience and time at your disposal - this is an enjoyable, therapeutic project but it takes ages and works best as a slow-burning, ongoing affair.