Add kefir grains or 240 ml of plain, active, live kefir to a non-metallic container.
Fill with milk, allowing enough space for the milk to release its gas.
Close the container.
Shake the bottle to allow the kefir grains to distribute within the milk.
Place the bottle on its side to allow the maximum amount of interaction between the kefir grains and milk.
Allow the kefir to rest at room temperature 70° fahrenheit (21° celcius) for at least 12 hours until the milk thickens as it turns into kefir. The keffir will continue to thicken slowly with time in the refrigerator.
Once the milk has thickened, refrigerate to slow the fermentation process.
Maintaining Kefir
Replenish with milk when 240 ml of kefir is left in the container and repeat process.