To register a new patient, you need to go to the PATIENT RECORDS tab and click the "Register New Patient Record" button at the top of the screen. 
When registering a patient, you specify their gender and personal data, optionally add a personal photo of the patient and type a note, if necessary. You have to understand that you can’t register multiple patients with the same phone number. If the patient is a child, there is a field for entering a parent's phone number instead of the patient's phone number, and you can specify the parent's name in the note. The parent's phone number can be the same as the client's existing phone number in the patient database. Here, you can also specify a permanent discount for the client, if such a discount exists. This column is of informational nature only and is not automatically applied when you accept a payment, but it appears in the modal window.
You can register a new patient both in the "PATIENT RECORDS" tab and in the "Schedule" tab when you create a new appointment (to register a patient this way, you should press "+" to the right of the patient’s file row).