- play defensive in early game
- try to get blue- and red-buff as often as possible
- use midgame to get kills and gank
- use W to slow (Engage/Escape)
- use Q to increse your speede (Escape/Engage)
- Spam E to lasthit minnions and heal your self
- Use R to reanimate an ally in big teamfights
- take the role of the tank in lategame
- STAY WITH YOUR ****ING TEAM

Pros

nice hp/dmg-output
insane ultimate for teamfights
slow
burst-dmg

Cons

squishy in early
hard to disengage
bad jungler

Early game

In Early game, Yorick is realy squishy and easy to get focused down by range-carrys – esecialy with exhaust on you. So i't up to you, to play defensive and try to finish minions and do some preasure with E. If one of your enemies are on low health, use W to slow him down, spam your abilities and use flash to get him or escape if nessessary. Don't forget to ceep using Q and E, to slow him and increase your movementspeed.

Mid Game

You now should have Manamune and your boots and it's time to play a bit more agressive. GET BLUE-BUFF! And spam your enemies with W and E. Maybe also try to gank other lanes with W for slow and then exhaust + Q/E Spam. It's insame, how much damage you can deal, while your opponent is trying to run away ;)
In this part of the game, you are acting as an carry and try to kill an harass as much as possible.

Endgame

In Endgame, when you have Atma's Impaler compete, you will still deal a lot of damage bacause of the AD-boost from mana and hp, but will more and more do the job of a tank. Try to slow the enemy team and take the dmg, while healing you with E. In teamfights, give your ultimate to allies, which are up to die, to bring them back to life for a few seconds which can dicide games.

NEVER try to jungle with him - realy don't work ;)

As the headline already says, i just wanna wish you a lot of fun with this new heros, which is realy not that bad, as so many people says ;)

Also, i apologize for my bad english. I wrote everything quickly without a dictionary and there are certainly a lot of mistakes.