Plan before the power cut. I'd dare to guess that most candle fires are people who have never really used candles, and not given any attention to making or buying safe brackets and holders.
The Amish and Mennenites have good candle holders.
In my trailer, I have a couple "cup hooks" in the ceiling, which can be used to hang a battery lantern, or a railroad style oil lamp. In the back corner by the bedroom, I have a metal pan for holding candles. (Used to be a 9 x 9 cake pan. Two sides turned up. Sides punched, and then screwed to the inside corner by the bathroom and bedroom.) It's relatively sturdy place to set a candle, very low risk of endangering anything.
I've taken to remelting candles, as a hobby. Lately, I do try to make them in glass jars, which might be safer than tapers or pillars.
For using candles, a good table or surface is needed. Lay down a pie or cake pan, in case the candle falls over. Keep curtains, papers, etc, away. Keep out of reach of combustible children, or cats soaked in kerosene.