Oscars are homomorphic animals. Which means that the male and the female animals do not have any different body parts. Still there are some people who believe that the male Oscar has a longer anal and dorsal fin. Venting is a good method to get them to mate. Moreover, keep the temperature of their water up to 80F, and keep the water very clean. The aquarium should be a tank of 284litres.
You can't really... At least not easily
The only way is to look at it's vent. Females' are larger and rounded while in males it's smaller and more of a point
The only way is to look at it's vent. Females' are larger and rounded while in males it's smaller and more of a point