In a sterile Agee style preserving jar place ½ teaspoon of Kefir Grains and 600 mls of milk.
Cover. a) With a sealed lid (so no oxygen is available is to your ferment) - this will reduce the yeast flavour and the fizz.
or b) With a cloth top such as muslin or a Chux Cloth for a stronger flavour
Leave in a cool(ish) place, just as the pantry for 18-24 hours to ferment
Test with a soon to see if it has set, it should smell slightly yoghurty or cheesey when done.
Once done, strain (add a drop of lemon for extra flavour) and refrigerate. (Your finished Kefir should last 7 - 10 days in the fridge)