Appointments Booking - Calendars - Calendar Availability
For each defined calendar you can set the available days in the week and the hours per each day in which appointments can be set.
You can also set days which are closed for booking.
To set the calendar availability go to the Schedule section in the plugin admin menu.
And choose the calendar you want to set or change the availability slots.
The Schedule Grid
The grid display each time slot of the week. Available slots are marked in blue.
First of all, adjust the schedule grid granularity to the session length period - to make sure the granularity of the schedule matched the session length set in the calendar setting. For instance, 30 minutes or 1 hour slots.
You can then mark the days and hours in each day in which booking is available. Note that you can select a series of slots at once with the mouse.
Exceptions - Days On and Off
Head to the Days On tab to add days that will be have available spots despite the week template.
Conversely, the Days Off tab allows you to set specific days that will be blocked despite the week template.
This is useful especially for holidays.
Since the version 2.3.5, you can specify a front-end label for a certain day off. You can also specify background and text color in plugin settings for such kind of booking slots.