First, and very important, make sure your firearm is unloaded BEFORE practicing with dry firing. Unload it in one room and then go to another to do your dry firing, leaving any ammunition in the first room. Then check again to make sure your firearm is unloaded.
Dry firing is an excellent way to maintain and even improve your shooting skills, but remember, make sure your firearm is unloaded when you do this! (I know this is a repeat from my Interesting Thought, but it is something you should really consider doing).
You’d be surprised what 5 or 10 minutes of dry firing a day will do for your shooting skills.
AFTER you’ve checked, double-checked and triple-checked to ensure your firearm is NOT loaded…
Find a safe place to point your firearm and then pick out a point (a nail head, a small screw, a small hole, etc…something small) and use that as an aiming point. Assume your firing position, line your sights up and press (squeeze or pull for you old-timers) your trigger. If your sights move when the hammer falls or the firing pin goes forward, you need to repeat the process until the sights don’t move (or move as little as possible).
Once you master dry firing from one position, start working on another. You can stand, kneel, sit, go prone, use walls and furniture as obstacles, etc. You can practice your presentation(draw) to get it smoother. You can practice lining your sights up and pulling the trigger after your presentation. The possibilities are limited only by your imagination.