You can set up your booking calendar at the start of the year and make any amendments when required, you can mark your venue as closed for Christmas or bank holidays, or mark as unavailable if you have any planned maintenance or expected closures within the year.
This is simply done through your booking 'Settings' within your Booking module.
Select 'Manage Calendar'.
A grid view will appear with months down the side and the days across the top. You can also make amendments to future years. You have a key for Open, Closed, Unavailable:
To make your venue closed, you would need to select the 'Closed' colour box in within the key and then select the days that your venue will be closed.
Remember to select 'Save calendar' once updated.
Once the date has passed then you will not be able to update and the grid will appear grey.