Hey, my name is ShinkeiFX. This is my first build on my favourite champion so far. Corki is a fun and really good champion to play. I had once played with him but I didn't really like him, then his IP got reduced and that is when I gave him another chance and I absolutely love him HIS DAMAGE IS INSANNEEEE. If there are any tips you guys want to give me, please tell me. :)
Feel free to add me on League of Legends!

Pros

+Great early-game harasser
+Great farming skills
+Insane late-game single-target burst damage
+Tanky
+Fun to play
+Nice escaping skills

Cons

-Needs to last hit very often
-Needs correct positioning
-Skills are very mana-heavy
-Range of attack is a bit less than a usual ranged champ.
-Low movement speed(Trinity Force makes up for it)
-No CC at all

TBU

Early Game
THIS IS VERY IMPORTANT. You have to be very efficient at LAST HITTING minions. Calculate the damage that a basic attack does and once the minion's health gets low, just basic attack it and you should be able to kill it. Keep practicing and you will start to have a feel for it. While farming, you would want to zone out the other champ as well by harassing with Phosphorus Bomb and a basic attack, remember that at this point Corki is very mana-heavy and so you should conserve your mana and choose when to harass and when to not.

COMBO AT LV.6/7+: Phosphorus Bomb + Missile Barrage. This combo should kill off waves of minions very quickly. This makes farming very quick and efficient.

As a carry, Corki needs his build nice and quick. Farming is essential to a carry, his Trinity Force is the core of his build... without it, he wouldn't be as efficient as he is now.

P.S. DO NOT tower dive unless you are confident you will make it out alive.

Mid Game
This is when you start to get ganked or start ganking. It is important to keep farming as much as you can, while ganking you want to head to a wraith camp every once in a while just to get some gold. Later on you can grab the red buff which is very useful for Corki.

By now you should have your Trinity Force.

Late Game
This is when Corki shines. Late game, he will drop other champions very quickly and very easily. His Gatling Gun is amazing and it only gets better the more the game progresses.
Still try to keep farming as well as aiming for champion kills whenever you can.