Using these mechanical decade counters is a breeze. First, snap the individual counters together according to your needs. You can connect as many or as few as you like. To start counting, use the up - counter button to increase the number and the down - counter button to decrease it. Remember, once you hit 9, it will automatically circle back to zero. As for maintenance, keep them in a dry place to prevent the PCB on the back from getting damaged. Avoid using excessive force when pressing the buttons to ensure they last a long time. If you notice any issues with the shorting of the contacts on the PCB, handle it gently and avoid bending the contacts.