RULE I: TREAT ALL GUNS AS THOUGH THEY ARE ALWAYS LOADED
RULE II: NEVER LET THE MUZZLE COVER ANYTHING YOU ARE NOT WILLING TO DESTROY
RULE III: KEEP YOUR FINGER OFF THE TRIGGER UNTIL YOUR SIGHTS ARE ON THE TARGET
RULE IV: BE SURE OF YOUR TARGET, AND WHAT IS BEYOND IT
The idiots in the video above showed very well just how important these rules are. I would add "Don't do drugs or consume alcohol around firearms". Surely my audience is sharp enough to not need that rule written down, but the wastes of skin in the video may.
Oh, and a side story about flares I picked up in the military. I heard from a guy who was deployed to Bosnia (third hand Army stories, take it for what it's worth) that they had trouble with a sniper showing up in the same spot night after night, and taking two or three shots at the base. The U.S. forces were not authorized to fire live ammunition, however, they were authorized to fire flares as a warning. So, the next day, said sniper shows up right on time, in the same spot as always. One cowboy decides he is going to actually aim his 40mm flare AT the sniper. The whole platoon lets loose with 40mm flares, pop flares, and pen flares. Said cowboy makes a direct hit on the bad guy, and the flare WELDS ITSELF TO HIS RIBCAGE!!!! Human flesh BURNS when exposed to extreme heat!!! The flare nearly killed the sniper, and managed to burn most of the skin and muscle off his upper chest. So the story goes.
Guns (and by extension, flare guns) are NOT toys! Follow the five rules above, or someone could get more than a scorched face! Acting a fool like this is exactly the sort of thing that gives the appearance of legitimacy to the anti-gun lobby. Every time you pick up a firearm, you are acting as an ambassador of the shooting community. What kind of ambassador will you be?
Oh, and stupid should hurt.