To create a new calendar, go to the calendar page using the menu on the left side or by clicking [CTRL+1].

Click the Calendar button next to the date. This will display a sidebar on the right side with your current calendars.

Click on the + New Calendar button.
Note: If no calendars have been created yet, then you'll see the 'No Calendars' message.

To save the calendar fill out the fields:
Click the Save button.
If the calendar was created successfully, then there will be a toast with the words 'Calendar Created'.