A.  For follow up appointments, you have two options. One is making a New TASK as an Appointment. In other words, an appointment you can check off on your to-do list.

To use this method (#1):

Navigate to the contact record to add the follow up appointment
Click on the +Task visible under the contact’s name
Fill in the name you’d like to see when it’s time for this appointment, select the TYPE as appointment, add the date/time, and check Display on Calendar. then save.

This shows up as a to-do item. It will be a to-do item on the Today Dashboard to be marked off as complete.

The other option is to make an APPOINTMENT It will show on the calendar, log an appointment on the contacts appointment history and (when connected) show on your Outlook Calendar.

To use this method (#2):

 

Navigate to the contact record to add the follow up appointment
Click on the +APPOINTMENT visible under the contact’s name
This will show on your Today Dashboard as an appointment (but cannot be checked off as complete)

There are two ways to accomplish based on how you wish to see appointments.