When in Ticket or Inspection list view simply click on Add new Appointment
Choose who you would like to create them for from the drop down list.
You can create an Appointment for a member of your team or for a Sub-Contractor.
Make sure to complete the Appointment field with enough information to help you or the person who you are setting the Appointment for, fully understand what's required.
Set the Appointment time and date using the calendar wizard.
Click Add Appointment to create.
That person you have set the appointment for will receive an email letting them know the appointment was created for them