The steps of sync Google calendar:
1. First download Desktop iCalendar and install it.
2. After installation is complete, attach your Google Apps account, enter your Google Apps account id and password.
3. Choose which calendars you want to add to desktop.
4. All events will be downloaded, and display on desktop icalendar, also user can open an event to edit, and then it will sync to Google calendar automatically, or you can sync it by manual.