So after loads of failed attempts to make yogurt throughout this cold winter ... I finally decided to get a yogurt maker. This will allow me to make my own yogurts whenever I want with no weird additives.
It's super simple to make your own yogurt with a yogurt maker ... you just need a yogurt (I make vegan yogurt) and 1L of milk. Start by heating 3 cups of soy milk in a pot and when it's hot, but not boiling (test it in your wrist). Switch on the yogurt maker. In a bowl blend yogurt with the rest of the milk and pour it into the hot pan. Switch off the heat and stir. Place the liquid yogurt into the pots and leave them in the yogurt maker for 8h approx. Get them out and place them in the fridge.
Make sure to use yogurt with a far away expiry date.