you have to complete each verse in almost one combo, don't get hit, and do it as fast as you can, if enemys are far, taunt to keep the combo going, also if taunt they get mad and that helps a lot to get more points for the combo (you can equip the item Gaze of Despair so all enemies are mad and if you complete the verses that way and without a single hit, its almost sure you get pure platinum)