Using this digital card multimeter is quite straightforward. First, make sure you have inserted the coin - type lithium battery (CR2032). Then, connect the test leads to the appropriate ports on the multimeter. You can start measuring DC voltage, AC voltage, or resistance by setting the multimeter to the corresponding function. The auto - ranging function will select the appropriate range for you. When using it, always ensure the test leads are well - connected and that there is no risk of short - circuits. Avoid overloading the multimeter beyond 500 V when using the resistance or continuity functions. For maintenance, keep the multimeter in a dry and clean place. If you don't plan to use it for a long time, remove the battery to prevent damage. You can also refer to the instruction manual for more detailed information.