I recommend that you start out making it by using just 3 tablespoons of sugar, 3 tablespoons of powdered milk, and 1 tablespoon of cocoa. Using this base, you can experiment to see what exact portions you like, and then make a bigger batch. Also, note that you can use the colour of the mixture to help you figure out whether it’s correct. Note the colour of the commercially bought kind, and compare it to your own to make it whiter (sweeter) or browner (bitterer). (-TomK)