Changing the default start day and time (web app)
Let's say your calendar starts on Monday at 6 a.m., but your business runs Monday through Friday, 8 a.m. to 5 p.m. In 'Calendar preferences' you can change 'Week starts on', 'Day starts at', 'Calendar slot size' and 'Show gridlines' (under Calendar view), plus 'Event default duration' and 'Slot frequency' (under Appointment window).
Go to your calendar and click the three dots in the top right corner.
Choose 'Calendar preferences' and set 'Week starts on' and 'Day starts at'.
Changing the default start day (mobile app)
Go to Calendar > Calendar Preferences.
Select your preferred starting day from the 'Week starts on' drop-down menu.
Tap Save in the top right corner to apply changes.
You can only change the day in the mobile app. To set a start time, head to the web app.
Note: Changes to 'Show income stats,' 'Show activity,' and 'Slot frequency' in Calendar Preferences only affect the logged-in account on your device, not the entire business.