I have some valuables in my home but nothing worth risking my life over. Likewise if I was walking down the street and robbed at gunpoint or driving in my car.
What I can I, in the situation of being subject to an armed robbery, do to increase my chances of not getting killed?
The first defense is always run away if you can. If you can’t run away, give them what they want. If they seem intent on killing you regardless, then you might as well fight. Get some DNA under your nails to help the DA convict them after they find your body.
Personally, I’ve always just been monstrously large with a resting murder face. That tends to encourage people to take their violence elsewhere, but it’s the kind of trick most people can’t utilize.
If you think there’s a real concern, get some self-defense training. Learning how to fight at a good school could help your confidence and preparedness. However, I’ll point out that any good martial arts school will also tell you that rule one is run away if you can. There’s no defense better than not being there.