Signal for help using the international emergency sign for distress, which is three of any signal: three blasts on a whistle, three flashes with a mirror, three fires, or three X’s on the ground.
Personal Locator Beacon
Personal locator beacons (PLBs) provide a distress and alerting system for use in a life-and-death situation. A PLB is a small transmitter that sends out a personalized emergency distress signal to a monitored satellite system. When you buy a PLB, you must register it with the National Oceanic and Atmospheric Administration (NOAA). PLBs are a highly effective and internationally recognized way to summon help.