Starting with the Summoner Spells, I take flash because it's flash and is great for any situation. I also take Teleport so that after a gank you can return to the mid lane quickly or it can be used in the late game to get from clearing a lane to back to your team. For Runes I take Magic Penetration marks to make sure that your spells are hitting as hard as they can. I then use Attack Speed seals to help proc the extra mark of the storm you can get from your basic attack. Cooldown Reduction glyphs so that you can throw your Thundering Shuriken every 2 seconds. Flat Health Quintessences for that extra health boost.

In the beginning of the match you should be last hitting like a champ because you need a lot of money for your first items before your boots. The one thing to remember is you are a flippin ninja and you use energy so don't be shy with your shurikens. Throw them at everything as soon as it is off cooldown. Until you are ready to kill the opposing champion. I suggest not trying this until you are at least level 4 that way you have level 2 shuriken and level 1 for you other 2 spells. Also finishing your Rylai's before your first lane kill will help by making sure they are slow enough to hit. If you can get a kill before this by all means take it, but i wouldn't recommend trying to rush a kill it's a good way to get messed up.

During the Mid Phase, you want to make sure to rush your Deathcap. The AP boost will help immensely. The next thing to remember is not to pop your ult prematurely. Make sure you have at least 2 enemy champions in range before you do and focus one down before you take the other down. There are a couple ways i recommend using your ult first is the most common way and that is to lighting rush into your enemies and then use your ult followed immediately with Electrical Surge for the stun. The Second way i would use it is to Shuriken, Surge, Rush, Ult. This way is more effective against more resilient champions because it allows you to get multiple stuns in rapid succession again a single target.

In the late game your job switches to strictly kill the other team. Kennen is an amazing penta kill champion if you use him properly. One of the most important things to remember is that you have a 2 second cooldown on your shuriken at this point so use it. The only problem is if you use it too quickly you can run yourself down on energy and not be able to use your rush when you need it. There is a balance that is needed to make sure that you are not over using your shurikens that unfortunately only comes with practice. Lastly your end game items should be Will of the Ancients first to give you some good spell vamp, followed by Void Staff for extra spell pen. and Abyssal Scepter to reduce and Magic Resist the enemies may have. The number one thing to remember in the end game is that you do not have amazing survivability so picking your fights is key.