Good advice here by some... here is my $0.02
Guns are tools. Have different tools for different jobs, hence why I have several sizes of guns and holsters
Train train train
Don't own guns and not own a safe if you have kids....ie - use common sense fucking morons.
Think long and hard if you can take a life. If you cant, please don't carry and get yourself and others killed.
Best advice many wont tell you...
KNOW YOUR LOCAL DEADLY FORCE LAWS better than the police
Have an attorney's number on hand. Even if you are legally legit in killing someone, doesn't mean their family wont try and sue you civilly in court.