Making Greek Yogurt Part 1 -- Equipment and Setup

This posting is subsection 1 of a series on how to make Greek-Style strained Yogurt.  Please start with the section title “Main Post”, then proceed to subsections 1, 2, and 3.
Ingredients

• Milk (Whole milk, 2%, 1%, depending on the fat content you want in the end product)
• Non-Fat Dried Milk Powder (about 1 cup per Gallon of Milk, more or less to taste).  We are using only the powdered milk to increase the amount of protein in the final product, not the additional water that would be added.
• Greek-Style Yogurt with active culture (Brown Cow, Fage, … ) Must have active live cultures. Look for “Greek-Style’” on the label.  Avoid yogurt that has additional ingredients such as gelatin or other chemical that might be used in some commercial yogurts to help thicken their product or prolong its shelf-life.  Do not freeze. Frozen yogurt is delicious, but the freezing kills the active cultures, and you can’t make more yogurt out of it.  Use 2 or three tablespoon of starter per batch, regardless of the total size of the batch.  After you take the tablespoons of starter out of a cup of yogurt, refrigerate the rest to either eat later, or to use as a starter in a later batch.  You can use your own homemade yogurt as a starter, but after one batch from home-made starter, I tend to go back to store-bought.  

Quantity
I make batches of yogurt starting with 2 or two-and-a-half gallons on milk.  As you are learning to make your own yogurt, I suggest you start with smaller batch sizes until you get used to the process.  As noted below, the amount of non-fat dried milk is variable to your own taste, and can also be omitted.  I think the additional non-fat dried milk adds considerable richness and additional protein, without adding more fat.
See notes below on equipment to make sure you have the appropriate sized equipment to make the batch-size you are choosing.  I once made a 5-gallon batch, only to realize at the end that I had to strain the resultant yogurt in smaller batches because I didn’t have a big enough strainer.
Equipment

• Pot, non-reactive like stainless steel or porcelain. Aluminum is not recommended.
• Strainer or colander. (The cheesecloth will do all of the straining, so it doesn’t matter how fine the strainer is.)
• Cheesecloth (Fine Mesh) I use a single layer of a very fine mesh cheesecloth. I get mine from Bed, Bath, and Beyond. The stuff I bought at my local grocery was way too coarse. You need a large enough piece to line your entire strainer.  If you need to double or triple the layers of cheesecloth, then you will need a huge sheet to line the entire strainer.
• Kitchen thermometer. All temperature readings below are Fahrenheit.  I recommend an electronic thermometer with a remote temperature sensor that can be left in the pot, with a wire connecting it to the display.  Mine can be set to ring a chime if the temperature falls below 100(F) or above 120(F).