Tips are added to catering orders through the POS.
If payment is collected at the time of order, a tip selection page should appear after selecting the "Credit/Debit Card" option.
If a tip is not added at that time, you still have the ability to adjust the tip
This is done by accessing the ticket through the Ticket History. After accessing the ticket there, there is a button that says "Adjust Tip". You can tap this button to then add a tip to the ticket.