First aid in an emergency, preparing yourself for an accident during an emergency is important. Be prepared that someone could get hurt, otherwise your problem will only get bigger than it already is.
Think of dressing wounds, pinching off large bleeding with a tourniquet, splinting, up to a bumped and open toe or large splinter. Anything can make your situation more difficult during your flight or home emergency. Make sure that nothing gets infected, wounds stay clean and that you can stabilize someone if necessary.