Different birds use different building designs: they can be huge or tiny, made of twigs, grass, leaves, or mud. But most birds follow a similar final
step in the nest-building process. They line the inside of the nest with
something soft, such as a feather.
Once eggs are laid in a nest, the parent birds will spend hour after hour
sitting on them to keep them warm and safe. They need that nice soft
lining for their own comfort.
This is probably the origin of the phrase "feather one's nest.” It means to
do something now that will provide for your own comfort later on.
Make a list of some things you can do now to “feather your nest."