Leave can be added by individual employees (if they have the permissions to do so), or they may be inputted by the managers/admin. If the manager/admin is inputted the leave of employees, however, they may also do so through the Working Schedule.
To add leave, you will need the Request Leave permission. If this is set to self, then you can only book leave for yourself. If it is set to a specific department, or specific employees, or global, then you will be able to book leave for others. To access the Working Schedule and add leave there, you will need Manage T&A Working Schedule permission.
How to book leave from the Scheduler
Go to the Time & Attendance section and navigate to the Working Schedule tab.
If you are viewing the schedule in a Monthly view, simply click on a day and the below menu will show:
If you are viewing the schedule in a Weekly view, and the schedule is already generated, clicking the red plus sign will show this menu. Click Add Leave.