You want to start of by rushing the sheen this well help your Oow alot when you use iver OoF or OoP after getting that get the 25% attack speed boots this is so you can get away and attack fast once you have that get the Phatom dancer so that when the build is done it will help alot because after that you will need the black cleaver which will take down there armor so that your minions can do more damage now its time for a bit more defence get warmogs then atma's impaler after sell your sheen and buy infinity edge so it gives you that attack damage and more crit damage since you will have good crit and good attack speed

Oman of War is your main move because it is a 1:1 AD ratio so more damage
Oman of Pestilence is your Aoe move it is a great push and it slows so that you can chase down your target
Oman of Famine is a great spell you can use it to heal yourself the amount of times ive had to recall when im on like 200 health also it can do alot of damage if you combo with it (Oow first then Oop so that they can get away then finish with Oof to heal you back up and to do 15% more damage because of your passive)
Oman of death is a great uti because if you get killed and your target is on something like 10% health you use it on yourself before you die and you get up then do some combos and kill your target before you die

to sum up this build will help you alot it will make you survive plus do alot of damage there is just one problem with the build and that is the mana but mid game you wont need to worrie about mana because your auto attacks will do loads of damage anyway also this is my first build i didnt see many for yorick well good ones anyway this worked for me please leave feed back would love to know what you guys/girls think!