It is highly recomended you don't use this build if you're the only champion building tank items, because you won't be able to tank all the damage by yourself. Your discretion is advised. Sorry for any grammatical error i may do, but english is not my native language.

Why pick WW?

Pros Cons

Fun to play Ultimate is a "bit" wiffy
Consistent dps Relies a LOT on movement speed
Sticky mofo Animations are kinda clunky
% health damage on very low cd Prepare your eardrums for actual drums the whole game
Gotta go fast Hope you like red
No lifesteal, no problem 1 effective cc
Easy to play & satisfying Not the tankyest dog
Powerful 1v1 and early game Easy to be played around
Long range cc (skillshot thou) Jungle clear item reliant(tiamat)

Marks
I would consider only Marks of Attack damage.

Seals
Get that armor to tank that early jungle with 9 Seals of flat armor.

Glyphs
Usually I'd pick Atk speed glyphs for the faster clear and maybe a couple aa extra for the early ganks, if the enemy team is magic heavy I'd get scaling magic resist glyphs.

Quintessences
Attack speed is the right stat to be efficient. You may want to get movement speed runes if you won't get boots of swiftness.

The keystone mastery for jungle is almost without doubt Fervor of Battle, the other keystones aren't as effective.
If you take the wolf top you might want to pick Grasp of the Undying as in that context is usable.

Warwick has a natual high sustain thanks to his q and passive so instead of the classic pots you want to get an advantage on that Tiamat by starting with Hunter's Machete and a Rejuvenation Bead.
You should be able to do a full clear of the jungle and pull off 1 gank or 2 before needing to back to base so you should have enough money to finish the Tiamat and buy tier 1 Boots; should you have enough gold I'd reccomend buy the Skirmisher's Sabre before the Recurve Bow.
Remember to always use the active of Tiamat at the start of any jungle camp to reset your aa timer and speed up the process.
If you feel that Boots of Swiftness aren't the right choice for the game you should limit yourself to Ninja Tabi and Mercury's Treads.
Standard tanky items are Spirit Visage and Dead Man's Plate as they combine with our werewolf kit best that any other, if you're building more tanky i'd suggest removing Guinsoo's Rageblade for either Randuin's Omen or Banshee's Veil.
If you want to go full tank pick the Cinderhulk enchantment instead of Bloodrazor.

Guinsoo's Rageblade maximazes WW offensive stats as Ad, Atk Speed and gives you that nice passive that doubles on hit effects that applies on: passive, Bloodrazor, Guinsoo itself, Titanic Hydra, eventually The Black Cleaver (not sure if it helps stacking Fervor faster).
Do note that connecting with your ultimate allows you to get 5 Guinsoo's stack pretty much for free.

With max Guinsoo's stacks, 19% atk speed in the runes, Bloodrazor and the w passive you can easily reach the cap 2.5 Atk Speed (going over it by approximatly 0,03% if I'am correct).
I you feel compelled, have a ton of gold and are confident in your skillshots you might want to sell boots for The Black Cleaver, reaching the 40% cdr cap and still retaining decent movement speed as long as you hit stuff.

I always start w and at the buff on the bot side to get the help of the duo lane.
Get q second and work your way to the second buff.
You should already be lv 3 by the time you get there.
Do not reactivate e early so you can enjoy that damage reduction longer.
Max w first for better ganks, better clear and jungle objectives.
Max q second for the raw damage and sustain, max e last cause duh.
Get a point in ulty whenever you can.

Smite in the jungle, Teleport in the top lane.
I prefer Ghost over Flash in the Jungle for it's lower cooldown and it's compatibility with the blood hunt.
Top lane both Ghost or Flash are fine.