To set calendar preferences...
-Click (Calendar icon) and then click Day, Week or Month to view your calendar.
-In your calendar, click Options > Preferences.
-Specify the following preferences for your calendar. These preferences are reflected only in your calendar and not other users' calendar.Days in week view - You may want to view only the 5 working days of the week or view all 7 days including weekends.
Work starts on - Choose the first working day of the week.
Day starts at - Specify the time your day starts at work.
Day ends at - Specify the time your day ends at work.
Weekly Holiday 1 and Weekly Holiday 2 - Specify your weekly holidays. It can either be Saturday and Sunday or any other day of the week.
Hide events ___ day(s) after they've passed -
On selecting this checkbox your event will not be available in the calendar after the specified m\number of days.
Hide declined events - If you decline an event, you can choose to not have it in your calendar by selecting this checkbox.
Specify the following to set reminders for the upcoming events in your calendar.
Events - When do you want a reminder for the event - 5 minutes before the event starts, 15 minutes before or more?
All-day events - When do you want a reminder for an all-day event - on the day of the event or before that?
Turn off reminder via email - On selecting this, you will not receive reminders via email for the events in your calendar.
-Click Save.
More info can be found here: https://www.zoho.com/crm/help/calendar/index.html