You can use the Parent Unit to set the alarm as a reminder for you to take care of your baby. 

Turn on and set the alarm when it is currently off: Press the MENU button when the Parent Unit is in camera viewing mode. Press LEFT or RIGHT to scroll to the Alarm icon. Press UP or DOWN to choose On, then press OK. Press UP or DOWN to choose 2h, 3h, 4h, 5h or 6h. Press OK to confirm your selection. 

Turn off the alarm when it is currently on: Press the MENU button when the Parent Unit is in camera viewing mode. Press LEFT or RIGHT to scroll to the Alarm icon. Press UP or DOWN to choose Off. Press Ok to confirm your selection.