Like Sailor said, you use the sink, not the stove. Make the water in the sink 10 degrees hotter than your target temperature. If you are going to 102 degrees, make the water in the sink 112. Record the temp of the milk, and then in 5 minutes come back and stir it and check the temp again. Did it go up 2 degrees? If it did, I'd leave it alone for another 5 minutes. If it didn't, add a little more boiling water, about a cup, not much. Wait 5 minutes.
I keep a record on the dry erase board on the refrigerator. This way you can tell if you need to heat up the water some more. Keep a big pot of boiling on the stove all during the cheese making process so that you dip out of it as needed. Then you can use it to sanitize your molds and cheese cloth before you use them too.