Step one: Be logged into the email you wish to sync the calendar to.
Step two: Click the [Add to Google Calendar] icon at the bottom left-hand corner of the calendar you wish to sync. Find some of the calendars here.
Step three: You will automatically be taken to your Google Calendar, and a pop-up will appear with the calendar names. Click [Add] to sync the calendar.
Step four: Toggle the calendars' visibility by using the checkboxes on the bottom left-hand side of the Google Calendar page.