In order to apply breaks to timesheets, you must first make your way into the "Timesheet" screen. Managers do this via the "Employee Management" area (see here for help). Employees do this via the "Empoyee Self Service" area (see here for help).
You can add breaks by clicking in the Breaks section and inputting a time.
To enter a time of 9:00AM, you can simply type 9a and it will recognise it as 9:00am. Similarly, for example, 530p will be recognised as 5:30pm.
If you need to enter multiple breaks, click the 'pencil' icon on the right hand side and the timesheet editor interface will be shown. You can then click the green 'Add' button to add another break.
Once you're satisfied, press the 'Apply' button.
After you have saved the break times you will notice that the hours under the "Duration" heading will change according to the break times that you have entered. So an 8 hr duration will automatically become a 7 hr duration after a lunch break of 1 hr has been entered.
Once a timesheet has been submitted, you are able to go back and edit breaks that have been applied. Simply click on "Approve Timesheets" in the Timesheets menu.
From here, you can either Approve, Reject or edit the timesheet - click the small "pencil" icon on the far right of the particular timesheet that you need to edit, this will open up the timesheet editor.