How do you beat kid buu on story mode for dragon ball z budokai tenkaichi 3

If this is your first time battling him, I definitely suggest putting the game on easy difficulty. When the battle first starts, fly straight up. Then fly to the side of the screen until you can go no further, using a dash (not the one that uses kai). Charge you kai. As soon as he comes at you, fly away. If he does a fast dash (he will have a bright aurora around him), guard. Knock him away as soon as he stops attacking and fly away. When you have enough kai, use your strongest move when close to him and run. Repeat this until it prompts you to change characters. Switch characters as soon as it asks you too. Eventually you should win.