[svtruth]

decock a loaded revolver?
If one were hunting and the animal spooked for a sample scenario.

[461]

Thumb firmly on hammer, pull trigger and let it ride slowly down to rest. Please practice the move with a "Double Checked" unloaded gun!!!

[HammerBite]

Do what 461 said, and . . .

If shooting a SA without a transfer bar:

Release the trigger in time for the hammer to catch the quarter-cock notch. This will keep it off of the firing pin and re-enable the cylinder bolt retraction so you can then pull the hammer back to the loading position and adjust the cylinder as needed to get the empty chamber back to the top. You do only carry five in your six-shooter, don't you?

If shooting a SA with a transfer bar:

Release the trigger in time for the transfer bar to withdraw from behind the firing pin.

If shooting a DA:

Release the trigger in time for the transfer bar to withdraw (if the gun has one) or for the hammer rebound mechanism to intercept the hammer.

[svtruth]

That is sort of what I figured, but it still seems a little hairy.
One advantage of an auto I had not considered.

[Ben Shepherd]

One more thought to add to the above advice:

You may consider having a smith checker the hammer spur heavily for more positive grip as well.

[GRIZ22]

See Hammerbite for SA without a transfer bar.

Riding the hammer down with your thumb works but to be safer with a DA or SA w/transfer bar:

1. Put your little finger between the hammer and frame so the hammer will fall on it. Okay it's just a little pinch.

2. Pull trigger so hammer falls on little finger.

3. Remove finger from trigger.

4. Remove little finger from hammer/frame and ride the hammer down.

This ensures the transfer bar or safety bar (inside a S&W) disengages and ensures the weapon won't fire.

This is the method I teach although I might might just ride the hammer down it's a do as I say not as I do (until you gain more experience) situation.

[HammerBite]

I have done something similar using the tip of my thumb instead of my little finger. I ride the hammer down to my thumb because it hurts like the dickens if I just drop it!

I have found that some single-action guns get a bit balky if you release the trigger too soon while lowering the hammer. The above technique does provide a useful gauge for when to release the trigger.