1. Check that it’s unloaded. Double check. Dry fire at something not living.
2. Oil as the instructions say. Try to get some oil in the trigger mechanism.
3. Black out the sights with 3 coats of black Sharpie. If you want to keep the dots on them, do so. You can also add your own dots.
4. Use a lighter, as well, to black out the sights, unless they’re plastic. Plastic will melt.
5. Feel the trigger pull. If it’s long and grating (like on $15 pistols) then pull it a 2-4 hundred times to break it in. If it’s good, a hundred times will do.
6. Shoot from a rest, or as steadily as you can, at an average distance for the gun. Note where the shots tend to go. After that, adjust the sights to correct where it shoots. If the sights aren’t adjustable, you can file down the front sight.
7. You’re done! Enjoy your better-than-new pistol! Make sure you shoot the correct caliber and type of ammunition.