Five days on tail, ears, eyes, mouth and how they combine — the quiet early signals almost everyone misses, what to actually do when you see them, and the one rule that keeps a dog's warnings intact.
Lip licks, yawns when nobody's tired, ground-sniffing, slow turns away. These come earliest, cost nothing to respond to, and are missed by nearly everyone — including people who know what whale eye means.
A growl is information. Suppress it and you haven't changed how the dog feels — you've removed the signal that told you. This is where 'he bit with no warning' actually comes from, and it's the most consequential thing most owners have never been told.
A wagging tail on a rigid body isn't friendliness. Knowing individual signals without reading them together produces confident misreads, which are more dangerous than knowing nothing.
Curled tails, floppy ears, heavy coats and flat faces all obscure signals that generic advice assumes you can see. Reading a specific dog means knowing what that dog can and can't show you.