How to create a Task from a calendar Event.
Click the green '+Add New' and select 'Event'.
Fill in the calendar event details. Don't click to 'Save Event' just yet!
Once you've added the event details, click the blue text 'Copy to task'.
The event details entered previously will now appear here as you create your new task.
Note: If you leave the 'Assigned to/Billing User' field blank, this task will be automatically assigned to your username.