Playing as warwick is prety easy. Either jungle or laning. I play him lane because I think his sustain is very good and the need for recall is not so important.

I use flat attack damage runes in quintessence and marks for the early high damage while also having the dorans ring.

In early game I buy dorans ring. Dorans ring is very usefull for warwick because his it affects his passive making him lifesteal more. Also his Q will heal him loads more and dorans ring will give you some nice mana regen so spaming frequently wont be a problem. Afterwards, you can just sell the dorans rings and replace them with the items above.

Warwick counted himself amongst the most powerful and revered men in his home city-state of Zaun. Over the course of his infamous career as an alchemist, Warwick won many honors for his craft, not the least of which was a lucrative offer for service in the Noxian military during their campaigns against Ionia. Sequestered in his labs far from the front lines, Warwick and his apprentice Singed toiled relentlessly to manufacture all manner of appalling concoctions for the Noxian army. So potent was his art that even the greatest of Ionia's healers - under the leadership of the Starchild Soraka - struggled to combat the poisons and chemical weapons generated by his despicable mind. Warwick's reign of terror grew so horrific that his very name became a curse in the eyes of his Ionian foes, and they began referring to him only as ''the Deathmaker.''

But even one under the protection of the Noxian High Command is not wholly beyond the reach of retribution. For as Soraka strode across the myriad of death and destruction left in the wake of one of Warwick's chemical attacks, her heart finally gave way. She called down the wrath of the cosmos on Warwick, wishing that his form should mirror the cruelty in his heart - a curse that would come at the price of her aspiring divinity. Within his laboratory, a terrible thirst took hold over Warwick. As his apprentice looked on in horror, Warwick threw open the doors to his bastion and sprinted off toward parts unknown, a bloodcurdling howling marking his passage. He had become a werewolf; a wild, murderous beast. Today, the Blood Hunter fights for Noxus within the League of Legends... thankful of the curse that his now-mortal enemy bestowed upon him.

''The rage of the beast now complements his predatory spirit.''
-- Singed, the Mad Chemist, upon witnessing his master's transformation