zWhen you hold the zero down until it beeps that puts you in alarm settings mode. You only need to hit the 0 once and you should be in the main settings mode. Once you are there arrow up or down with the 2 or the 8 to find clock settings press 5 to open this feature. Your choices are hour minute day date month and year and am or pm to set each of these use the 4 and 6 keys to adjust up or down when you have them all set the way you wish press 5 to accept.