Select subscribe and it will prompt your phone to add the calendar.
If your calendar doesn't automatically accept subscriptions or you are on a computer, please follow these instructions for Google Calendar:
1) Open your Google Calendar and click the gear icon in the upper right-hand corner and select "Settings".
2) Click the Add Calendar menu option in the left-hand sidebar menu and choose the "From Url" option.
3) Copy the calendar link below that you want to sync and paste it into the From Url box and click Add Calendar.
