Learn to decock
There are quite a few votes for "decocking accident."
I see the way people decock a gun in the movies, and I hear about ND's with a 1911, or a revolver that has a transfer bar or other safety mechanism. So I know that some people just don't get that there are some safeties built into many modern guns which they are inadvertently bypassing.
The way I do it seems pretty safe. What do you think?
After pointing in a safe direction, I:
1. jam the tip of my thumb against back of the slide, between hammer and firing pin. I will never pinch the hammer between thumb/forefinger, because the only thing stopping the hammer from falling in that case is friction. The hook of my thumb holds the hammer back. But this is secondary to the first thought, of blocking the firing pin at any and all cost - even if it results in pinched skin.
2. put finger in trigger guard, and pull trigger
3. remove finger from trigger guard, because:
a. This engages the trigger safety, if the gun has one!
b. Holding the trigger and the hammer back at the same time is more complicated for my puny brain.
c. Index finger along the slide gives a better grip/leverage/control for the next part.
4. lower hammer, keeping thumb pinned to the back of the slide, and just sliding up and out of the way when necessary.
5. if there's a half cock notch, then I deal with it after it engages. I don't keep the trigger pulled all the way down, just because I'm too lazy to pull it again. A gun is less likely to ND from the half-cock notch.
I do not practice this to make it smooth and automatic. I think about each step as I go, every time I do it, whether I know the gun to be loaded or not. If I can't give this process my full attention, then I'm better off leaving it cocked. Manually decocking a gun requires you to violate one of the most basic and important of gun safety rules. It should never become automatic, IMO.