Here is my simplified way of making yogurt. I love it!
1/2 gallon raw milk (pasteurized milk will work, too)
4 TBSP plain greek yogurt
Place 1/2 gallon of milk in large pot. Heat on stove until it just comes to a boil. Turn heat off.
Let milk cool to 100°F.
Take about 1 cup of milk out and mix with 4 TBSP plain greek yogurt until thoroughly mixed. Add mixture to pot and stir.
Pour milk into jars or bowls. I use quart jars.
Place in bread proofer or oven set at proofing option. Set temperature to 110°F. Leave undisturbed for about 8-10 hours. I mix up a batch before I go to bed.
Take a collander and line with cheesecloth. Dump yogurt into cheese cloth. Tie the top. Place collander over a bowl and place in refrigerator for about 45minutes to 1 hour. The longer you let it strain, the thicker the yogurt will be. Remove yogurt from cheese cloth and place in a covered bowl and place back into refrigerator.
When ready to serve, add sugar, vanilla, frozen or fresh fruit to your liking.
Save about 1/2 cup of the yogurt before you sweeten it to use as your starter the next time.