signs of dominate behavior

A few things to watch for is a definite change in posture when seeing another dog. Tail goes up, maybe with slight wagging, but not wagging like crazy. A quiet stare, and instead of sniffing the dog will immediately move to put his muzzle over the other dogs back or shoulders and may even put a paw up on the other dogs back or shoulders. At that point if the other dog does anything but completely submit there will be a fight.