OK, so just to point this out, which I'm sure everyone knows, different pistols operate quite differently. Here are a few examples, top to bottom:
CZ .380 SAO: Cannot lock slide back, does not lock on empty mag, must have mag in to fire, no decocker
S&W 459 9mm SA/DA: Can lock slide back, locks on empty mag, must have mag in to fire, decocker
Ruger Mark II .22 LR SA: Can lock bolt back, locks on empty mag, fires without mag in
Hk VP70Z 9mm DAO: Cannot lock slide back, does not lock on empty mag, fires without mag in
Davis P-.380 SA: Cannot lock slide back, does not lock on empty mag, fires without mag in
Some of the basics apply to all of them: Remove mag, rack slide several times. The visual check can also be done, but how are you going to "pinkie check" a chamber when the slide is going to return to battery on your finger? I have big hands and even my pinkie may not fit tight enough to really check the chamber on a smaller pistol. A wooden dowels or even a straw can be inserted in the muzzle and pushed back to show the chamber clear. I know the straws we get with iced coffee from Dunkin Donuts are a fairly bright orange, or the dowels can be painted any florescent color (orange or green come to mind) for better visability at the chamber end.