Continuous Wake-Up Call (for very heavy sleepers)
Create a Google Calendar called Wake-Up Calls. In your Google Calendar channel settings, select that calendar. Add recurring daily events to the calendar based on when you would like to get your wake-up calls (I have events every 15 minutes from 5:00 AM to 7:00 AM). When you are fully awake, go to your Google Calendar and delete only today's occurrences of the recurring events to stop the calls for today.