I used to wonder how people in places like Texas and Australia ever survived before air conditioning. After a week with ours on the blink, I'm beginning to understand. They managed by working with nature, rather than against it, and by building houses a lot like this one which we live in now.
They had light colored metal roofs, to reflect the sun overhead, and deep porches and eaves, to protect from the sun's slanting rays each morning and afternoon. They had large, screened windows on all sides, which can be thrown open to catch those cross breezes, and ceiling fans in every room.
They had thick, well insulated walls, and sometimes even half-buried their homes in the earth. Our lower level backs up to solid earth, which gives it a cave-like feel and a fairly steady temperature year-round.
But, most importantly, they took siestas in the afternoon!