I'd like to test electric capacitance of different powders pressed into solids. I want to know if my procedure is correct. First I connect a wire between the material and a ground (ex. radiator) to discharge the material. Then I disconnect the wire and connect red terminal of the multimeter to the material and the other (black) to the ground (radiater). I repeat the discharging procedure before every measurement. Is this the correct and required procedure to follow?