As soon as Kazdan Paratus touches the ground, quickly start hitting the Force Lightning button, which is typically the Y button on the Xbox 360 controller, and the Triangle on the PlayStation 3 controller.
After you have hit him with Force Lightning, run up to him and knock him off the platform by using the Force Push. Hit him with Force Push repeatedly, instead of stopping after the first hit. Instead of holding the Force Push button, typically the B button on the Xbox controller and the circle button on the PlayStation 3 controller, pressed to charge it, just keep tapping the button to use the ability in quick succession. You do not need a charged Force Push to knock Kazdan Paratus off the platform. Stay on your toes after you have knocked him off the platform, as he will fly back up and most likely land wherever you are standing.
If you are unable to knock Kazdan Paratus off the platform using Force Lightning and Force Push, just stun him using the former ability and then quickly run up to him to attack him with whatever lightning combos you know. You can pick, impale and even throw Kazdan Paratus off the screen while he is stunned.
After you have successfully hit him with the Force Lightning and Force Push combo a few times, he will get really angry and spawn a huge creature. Hold the left trigger and Y button on the Xbox 360 controller or the triangle button on the PlayStation 3 controller, to charge your lightning shield to full power while the creature is spawning. Once it has spawned, stand close to his foot and unleash a flurry of combos on him. Having your lightning shield to Level 2 or more will allow you to constantly electrocute and stun it, thus preventing it from defending itself and consequently making the job even easier for you.
Once Kazdan Paratus comes back down, start using the Force Lightning and Force Push on him again, until he flies off and starts throwing chunks of metal at you. Dodge the chunks of metal and wait for him to come back to the ground. Once he does, knock him off the platform using the Force Lightning and Force Push combo on him.