You can add sick hours on your timesheet by clicking into the sick leave section for that day and entering the total amount of time taken in 1-hour increments. You cannot add more sick time than what is available or submit partial hours and your total hours for the day cannot exceed 8.  If you cannot access this section then you have no sick time available to use. 

You can view your available sick time balance in the timesheet section of your portal by clicking on the 'i' next to the 'sick' heading: