Get the yoghurt starter to a warm 36 deg C to allow the bacteria to develop.
Heat the milk to 85 deg C.If you don't have a thermometer, this is when the milk steams and begins to form bubbles.
Let the milk cool to 43 deg C . This is very warm to the touch, above blood temperature.
Stir or whisk in the yoghurt starter. If using a bifidus bacteria culture, blend into the milk with a stick blender to prevent it from forming in a stringy texture.
Incubate the mix at approximately 38 deg in a prewarmed oven or over steam until it sets, usually 4 hours.
Refridgerate to firm and slow the acid development.
«keep the yoghurt warm while it is setting by wrapping in kitchen cloths or blanket and sitting on a radiator. If wanting a thick Greek style yoghurt strain over a clean kitchen cloth for several hours . The liquid that drains off is called whey»