I just put the raw milk in an Instant Pot with about a cup of plain yoghurt and press the 'Yoghurt' button. Takes 12hrs, then I cool it in the fridge for another 12.

https://m.youtube.com/watch?v=_h1UdbT7QRM&pp=ygUQcmF3IG1pbGsgeW9naHVydA%3D%3D