What did gladiators do before fighting?

According to Wikipedia: The now famous gladiatorial salute "Ave Caesar, morituri te salutant" or "Hail Caesar, they who are about to die salute you" is another product of movies. This salute was only mentioned by Suetonius (Lives of the Twelve Caesars, Claudius, XXI, 12­14) as happening once, spoken by condemned men (damnati) to Claudius at a naumachia (a staged naval battle) and they used the Word "imperator" (Emperor) not Caesar.