While some meters are digital, most meters have four or five dials. The dials move alternately in clockwise and counterclockwise fashion. When a hand on a dial is between numbers, always use the smaller number (remembering to use 9 when the hand is between 9 and 0).
To calculate the amount of energy used, subtract the reading taken at the beginning of the period from the reading at the end of the period. The difference is the total energy used in kilowatt hours.