For employees who haven't worked and are not to be paid in the current pay period (i.e., casuals), leave them in the drop-down. If the employee is selected in Wages, no entries will be made, and it will not be possible to save the pay slip. A pay slip can only be created if there are any entries on the pay slip, even if the net pay is zero.
Days not worked aren't entered on the timesheet; instead, enter these as LWOP on the Adjustments screen. The Adjustments screen is located when you click NEXT on the timesheet screen in Wages.
If you have casual employees who won't return for a while, you can put a termination date in the employee record.
To do this, go to Employment, Employment, and fill in Terminate: and STP Cessation Reason:
By populating the fields in the employee record, they can be removed if the employee returns.