Notes can be added on the POS side from the Customer View or Edit screen. (Not sure how to get there? Read this article.)
You'll see the notes in the left side module on the Customer screen. Each note shows when it was added, by whom. If you want to delete a note, use the red X next to it.
IF you need to add a note, click on the + Symbol in the header of the notes section:
The Add Note screen will appear:
Type your text. At the bottom, you can click on the "Do not alert on lookup" to change it to "Alert on Lookup"
Save your changes.
IF you have set the note to Alert, it will appear in a pop-up when the customer is selected.
Notes can also be managed from Manager Home > Customer. Read This to learn more about managing notes from there.