As it says in the beginning, there are two targets, the body and the tail. Start by attacking its tail. Once its tail is gone, the camera will shift and its body will become vulnerable. Then Aya Brea can just finish it off.
As for attacks, it really likes using its claws and tail, and will use both if you get close. If it runs at you, then it'll try to hit you with two powerful swipes. It can also launch a series of shockwaves from its tail. In phase two of the fight the tail shockwave attack is replaced by one where it breathes three streams of fire in your general direction. In both stages of the battle, just try staying next to it or behind it.