If you need to learn how to make appointments first, check out your How to Create Appointments article in your Knowledge Base.
Once your client is ready to pay, click the client's name on their appointment and Add Client To Sale.
The client and their appointments will be taken across to POS (even if the services are spread across multiple operators).
If they would also like to purchase some Products, click the Add Items link and check out the options.
At this point the client can add any one of these items to their bill; an additional Service, Product, Gift Voucher, credit to their Account, Future Services, Salon Packages or a Variable Voucher.
Make your selection, and use the menu on the right side panel to choose the item, and Save it to the sale.
When the client has all of their items in POS, click Receive Payment, choose payment type and Finish Sale.
You might have a Rebook Reminder pop up if you have enabled this setting in your Cash Register Settings, in Settings.
Bill paid! The clients appointment will turn grey to indicate that it has been paid for.