Ohm
Member
The proper way to do it if you must, is to use your off-hand thumb between the hammer and the rear of the slide so there is no chance of the hammer hitting the firing pin. Push a bit down with your thumb until you just feel the hammer move so it can't get a running start to pinch you. Then pull the trigger and slowly move your thumb out from between the hammer and slide, up towards the rear sight. The hammer will ease down with nothing to slip as your thumb comes up and out.
Why do it at all? Why have a gun in a state between "loaded and ready" and "unloaded, cleared"?
Seems the worst of all worlds, a loaded gun which is not ready to fire when you need it to. And you have to pull the trigger on a loaded gun and hope you don't have a "problem" with the gymnastics to get it into this "twilight zone" condition.