BobbyM's installation guide is great. One thing I don't remember if he mentions is that for calibrating, if you can weigh the water rather than measure it by volume, you'll be a lot more accurate. If I remember correctly (double check to be sure), a gallon of water weighs about 8.34lbs. If you can measure out 4.17lbs repeatedly, you can have nice accurate markings down to a half gallon.