Just shut the main breaker off. Always the first step.
I agree. But my new house was built with the main breaker OUTSIDE, and I have to remove 4 screws to open the cover to access it. The lates National Electric Code is ridiculous with this requirement. So for me to shut off the main, I have to go outside, presumably in a storm or cold weather, remove 4 screws, take the cover door off, and trip the main breaker. All so that I can run my house on a backup generator or solar. That, my friends, is insane.
Actually, for my backup source, I'm getting a manual transfer switch. Although I may hold off and look into solar. Just have no plans to pay big $$$ for something to be installed by a greedy solar contractor.