The Google Calendar Glassware card will appear on your timeline to the left of the Home screen whenever there is an event on your calendar within the next two days. Multiple events will appear together as a bundle.
Tapping on a bundle lets you browse your upcoming calendar events. Tapping on an individual card gives you more details.
Tap again to make Glass read the details you, get directions, accept or decline invitations, or remove the calendar event.
Change the details of events that are already on your Google Calendar by tapping the event card. If you are the owner of the event, you can change the title, time, location, or delete the event. If you don't own the event, you can accept or decline an invitation to the event, or remove it from your agenda.
To change a field, just tap on the appropriate option, and Glass will allow you to dictate the new details.