mentor help continued

Sorry that you did not hear from me a long time but I was in a dark place for a long time. but im back and have a question I have to make a clock so the seconds and minutes schould not be above 60, How can I take care of that ? and can I put the code here on the class side on this given method hour: anInteger minute: anInteger2     self shouldBeImplemented or schould I use that to make a call to the instance side and take care of there that the seconds and minutes are always valid. Roelof