Clarity ~ Why clarity on someone like Yi? Early-game and mid-game, Clarity is great because of the fact that it's buffed from the patch. It also helps him keep his MP up and spam Wuju + Highlander. Along with the occasional Alpha Strike.
Flash ~ Because Flash is awesome. :3
Exhaust ~ Couple this with its mastery, and it makes a great ganking tool.
Heal ~ Yi can be very squishy. Valuable when escaping or early-game to regenerate without recalling from harrassment.
Runes, I'm not too sure.
For Quints, I would go for bonus attack damage or armor pen.
Marks, Armor Pen. (Whcih is nearly +18% armor pen)
Yes, Wuju Style first. Some people might prefer Alpha before Wuju, but I prefer Wuju over it. It lets you gain +15 attack damage at level one. It's good for hit and run on champs.
Now, for my item build. I've had loads of success with it...
Boots of Speed + 2 HP Pots (build into Beserker Greaves ASAP)
Malady (Either build or get the 1.9k needed for the entire thing)
Phantom Dancer (Zeal first, then 1780 for the Phantom)
Frozen Mallet (Phage then FM)
Bloodthirster (I usually wait and shell out the 3.2k all together since I usually have a lot of kills. If not, BM Sword first)
Last Whisper (Bow first, if you're anxious)
You're asking why I chose this?
Boots of Speed allows Yi to have 380 Movement Speed instantly. He also has the highest base mspeed.
Once that is done, you can get Greaves. You usually have around 1.0 Attack Speed at this point.
Malady for the life steal and +50% attack speed. It's unique passive isn't bad either.
Phantom for critical and movement (441 with it)
Frozen Mallet, if you're not using lizard, allows you pretty much a sure kill with Wuju active and Highlander.
Bloodthirster to up your damage by a lot. Also more life steal.
Whisper for armor pen and MORE attack speed.
You want to harrass with Alpha on a MINION and not the champions, unless they're alone. You're incredibly vulnerable early-game. But you can also deal some heavy damage with Wuju. (Don't activate it unless you know you can kill them) An occasional gank and whatnot isn't too bad either.
Now, this is where Yi makes his presence known. You've got Highlander and Wuju, nearly maxed. You will do CRAZY damage. Couple this with lizard, and you can feed and feed and feed. More than likely, if you don't have lizard, you won't get a kill. So, careful on that.
You should be at 4/6 on your item build. You can basically burst down anyone with Wuju + highlander due to your armor pen. :P
Yi is incredibly squishy. Never chase unless you have someone backing you up or you know you will get the kill.
Don't be afraid to pop Wuju and highlander on a turret. Taking a turret can turn that lane around for you easily.
Jungle often. Dragon early if possible. Gives 200g-ish gold and exp to everyone. :P
You can chase after someone, use Alpha, the immediately attack them if they're low on HP.
Comment below rating threshold, click here to show it.
Why is this necessary? Do I search for Master Yi and you will find 6 or 8 guides already, and 2/3 of them say the same thing. You presented nothing new here. If you don't have your strategy fleshed out enough to even be able to properly suggest runes, you don't need to be writing a guide. A few sentences on strategy. Same skill and item builds as everyone else.
I'm glad you are seeing success with Master Yi... but this is really pointless. Do a forum search.