In a survival scenario, it's important to do everything you can to remain self-reliant. Obviously that doesn't mean that you should always venture out alone, or that you should disregard the needs of your family and friends — a survival support network is helpful and can make your life much easier during a disaster. Self-reliance means that you can still get by on your own if necessary.
However, there are some situations when pure self-reliance becomes impossible. If you topple off a ridge and break your back, get stranded at sea, or become so ill that you're unable to walk, signaling for rescue may become your only hope for survival. Therefore, it's important to consider the best methods to indicate your distress and call for rescue.
In the following video, British survivalist AlfieAesthetics covers three categories of man-made distress signals: noisemakers, daytime signaling devices, and nighttime signaling devices. Noisemakers include whistles, car horns, firearms, loudspeakers, or just about anything that can produce a repeating pattern or S.O.S. signal (…—…) in morse code.
Daytime and nighttime devices have some crossover; for example, flares and signal fires are effective around the clock. Other items are only effective at certain times — signal mirrors and smoke signals will be most effective in full sunlight, while glowsticks and flashlights will be most effective at night. Finally, Alfie discusses natural signals, such as arranging sticks or rocks in easily-identifiable patterns that would be visible by aircraft.
Check out the video, and consider which options would fit best into your bug-out bag or emergency kit: