When adding Personal Appointments to calendars you have default options (Break, Leave, Meeting) but often these 3 types are not enough. You might want Team Meeting, Client Debrief, Client Handover or other. You can add any personal appointment type you want in Better Bookings.
Add Personal Appointment Types
Or go to Settings > Personal Appointments Type pod bottom right
Click 'Add Appointment Options'
Add the name of the new Personal Appointment type
Once added, this new type will be available when you're making Personal Appointments.