So i will lay this out in three section Early Game, Mid game, Late game

Early Game- For this build it is best to lane with someone that can either hit hard early game or that can stun or slow. with his passive you should be able to farm minion well and making sure to hit the enemy champs if you get a chance to make good use of his passive. having someone with you that can do good early game damage and or stun or slow should allow you to get early kills by initiating with the E-Q combo and having you and your friendly champ go in with you

Mid Game- By this time you should have your first Phantom dancer and working on you infinity edge. this is where you dont want to start initiating but more about picking your targets to gank REMEMBER his E-Q combo is great for both setting up a kill and getting away from other champs. Also by this time you should be able to solo Dragon

Late Game- by this time your build is mostly done and you DONT want to be the first person in the battles. this is because by now ppl should be noticing the damage you do and will start to focus you so for the best chance of success wait in bushes until your team initiates then join the battle that way enemy champs are focusing your other teammates giving you a chance to deal max damage to all enemy's. Also remember with Wriggles that u can use the jungle to get your health back with the life steal and to ward baron

PROS

-Very hard hitting
-great for ganking
-makes great use of his skills

Cons

-Squishy
-should not initiate

With this build u wind up focusing on attack speed and the damage output by crit. So as u can tell by the ending stats this Jarvan isn't tanky at all but it will do some heavy damage in a matter of seconds. Being able to crit ppl 80% of the time while in Jarvan's ult is pretty much an instant kill. Make sure that you let ppl know that you are not going to be a tank. this build really utilize the E-Q combo while they pop up for that quick second you can deal heavy damage and should also be able to get early kills with him. plus with the Wriggles make sure u use the free sight ward. for the last item i go Whisper but really it all depends on your situation. For example you might instead want to get a Blood Razor if they are all kinda tanky.

These Runes focus on Early game attack speed to farm better and armor pen thus to get an early kill

-Cloth armor and 5 potions are great to start with for the longer laneing and to build into the Wriggles
-Wriggles is great for the life steal, armor and damage early game and the free sight ward goes a long way
-Berserker's Greaves give that extra attack speed for early game
-the 2 phantom dancers are great for the attack speed and crucial for the Crit chance also gives u that extra speed boost to catch up and or to run away
-Infinity Edge great for damage, Crit chance, and the passive with the 250% crit damage helps even more
-Last whisper great for the damage and armor pen this is the one item i feel is replaceable if u felt like adding something different

Teleport- is great for saving turrets or backdooring. since you build alot of attack speed Jarvan can backdoor well with this build if need be

Ignite- a great way to finish any champ of eary game and if they just get out of ur melee reach

Its good to lvl his Demacian Standard first for the bonus attack speed and to check bushes then his Dragon strike followed by his Golden Aegis and of course get his Cataclysm at lvl's 6-11-16