DD, the easiest way to make yogurt - Boil about a litre of milk (I prefer full fat - you can use less fat, but not so much that it's non existent. Yogurt needs some fat) . Cool it down completely. Turn the heat back on, till it's just a little over warm - enough that you can dip your hand in it, but not boiling. Take about 2 1/2 tablespoons of pre-made natural yogurt (no preserves), mix one and a half spoon in the milk with your hand (yeah, I know it's a little messy, but I've found that the introduction of any spoon in the milk makes my yogurt curdle) really well. The best pot for making yogurt is either an earthen pot (which you have to season first - a little bit of work), or a plastic casserole (the bowl, not the dish) - like this one Rub the one spoon of yogurt on the inside of this bowl as well as you can, and pour the milk + yogurt mix into it. Shut & seal the lid, and let it sit undisturbed in a corner of your kitchen for at least 4 hours. Open it after this time has passed and shake the bowl slightly to see if it has set (kinda like checking if a tart is done). If not, reseal the lid, and leave it for another hour or so. If it has, put the dish in the fridge immediately. Most of the time, yogurt gets messed up cuz of the whole setting vs refrigeration time. When you need to remake, simply take a couple of tablespoons from this batch and repeat. It'll work. It always does.