Few clinics prefer to book appointments against non providers like Technician, Boarding, Nurse etc. It is very simple to show them on the calendar. You just have to create them as a staff and set them as a provider. Please do assign schedule so that they are available on the calendar to book the appointment. 

Follow below steps to create a staff and add schedule. 

1) Please click on the setup widget as shown below then navigate to organization and staff list.

2) Click on edit staff. 

3) Please select Yes for "Is user a provider." Click on save.

4>>  Click on "Assign to multi clinic and schedule" to setup a schedule for the staff.