A summary of the information about chariot racing that can be found in Ovid’s “Amores”.
The races were held in an oval-shaped stadium. The charioteers would usually have four horses, decorated in the colour of their respective faction (white, green, purple, gold, blue and red)*. The teams began the race behind a starting gate, to be released by the preator. After each lap had been completed, the supervisors of the event would turn over one of a series of miniature dolphins. The last dolphin would be turned over when the race ended.
Unlike in the ampitheatre, the stands at a chariot race had males, females, adults, children, masters and slaves sat together. Before the race began, there would be a procession of the gods, in which statues of various Roman deities would be wheeled out. Those mentioned in the Ovid extracts are Neptune, god of the sea; Mars, god of war; Phoebus, Phoebe, Minerva, Ceres, Bacchus, Pollox, Castor, and Venus. Spectators would use this time to cheer, and pray that their faction would win. Should one of the charioteers make a false start, or have to be stopped, the citizens of the crowd would flap their togas in disapproval. Due to the often violent nature of the races, charioteers would tether themselves to the reins to avoid falling off after hitting an opponent. In case this instead led to them being dragged along the ground at high speed, they would also carry a knife to cut the reins away, though this still left them open to being trampled by another team.
*Initially there were four teams. Under Domitian, more were briefly added including purple and gold.