While the oil is heating up, wash and pat dry the fish with a kitchen towel.
Season both sides of the fish with salt. There is no need to season ahead as it will dehydrate the fish.
When the oil is hot, slide the fish into the wok, skin side down. If the fish is big or if there is no skin on one side of the fish, cover leaving a gap so that it does not splatter. If the fish is small, then there is no need to cover.
Do not touch the fish until one side is completely cooked, about 5 minutes. Make sure the fish skin is golden brown before you flip it.
Flip the fish over.
Cook for another 3 minutes or until the fish skin on the other side is golden, if there is skin on both sides of the fish. Otherwise, cook briefly, about 2 minutes.
Dish out to rest.