I use a heavy, heat-proof jar, and sterilize it by pouring boiling water into it and letting it stand, then draining it well before adding the yogurt mixture. Swaddling the jar with a towel is a good way to keep it warm if you don’t have a warm place in your house or apartment. I’ve never made it with low fat or reduced fat milk because I like whole milk yogurt. People do say it works although I haven’t tried it. Be sure to use a brand of yogurt that has live and active yogurt cultures in it. Buttermilk won’t work, which I learned from experience the night before ; )