It's not all the that hard to understand it just needs to be explained in plain terms, check out this website, just skip over the chemisty section. Dave first thing get a small clear plastic cup, the ones you buy for refill for bathroom cups, the little one the dentist give you. Then see where the fill line on the PH meter is then mark that on the cup. The point is you want to get the smallest sample so as to not waste milk. This means do not put the PH meter directly in your milk, always take a sample and then throw the sample away. I've been using the same cup for years, just rinse it everytime, as you'll be taking about 5-8 samples per batch. Just make sure to rinse the PH meter in distilled water after taking a milk reading. Just have a glass of distilled water by and just dunk and swirl, then take your milk reading, then rinse in TAP water before putting the cap on. You don't want to store it with distilled water. Inside the cap will be about 1/8 - 1/4 tsp. of liquid to keep the probe moist. If you didn't buy storage solution just use tap water and recalibrate every few months.