You max your Q first because it is a safe, somewhat accurate poke that you can use to get farm, so you can get more stacks of Phenomenal Evil, because if you do that, you will get way more AP. You max W second, because it will deal huge damage in the mid to late game. You max your E last because you don't need to constantly cast your stun cage. Remember to use your R as an execution, but late game, it will pretty much just be a one-shot.

All you really need to know about items is to buy Rod of the Ages first, so you can quickly get stacks, get your CDR boots, and then get Rabadon's to give your AP a super big boost.