cut the tinfoil into small squares.
wash & towel dry your hair.
mix up the bleach powder and developer in a plastic bowl with the tint brush, i feel like its a 'frosting' consistancy.
both people should wear old clothing as bleach will immediatly damage anything it touches.
Starting at the back of the head and moving up to the crown (this is very important!) The person bleaching the hair divides up the hair into chunks and brushes the bleach into the hair, get close to the roots but dont get the bleach on the scalp because it will itch a lot.
After each chunk of hair, fold it into the foil. my lovely assistant crunched the foil, but thats not advisable as its harder to remove without yanking the rather delicate hair