Hi guys! I have just started a new build based on KT Insec. 1 of my favourite champs and I find myself playing him every day! He is 1 of the best junglers in LoL, if not the best. Play Video
This video showcases the many different types of plays you can do with Lee Sin. Hope you will enjoy playing him as much as I do! Credits goes to 7GUNEYTURK for the video.

Taking Attack Damage Marks is viable as it gives you the early game edge you will need.
Taking flat Armor Seals is also a good idea as it gives more sustain in the Jungle and ADCs will do lesser damage to you.
Magic Resist Glyphs are also a good source of Defence. Nuff said. :P
Similar to Marks, it gives you the early game edge and you can rush your items, allowing for more incredible plays and you would be the centre of attraction! :D

Start with a Doran's Blade as its passive kind of goes well with his Flurry as it gives Attack Speed, allowing you to hit more times. Taking 3 Doran's may sound stupid but in actual fact, it's actually a good idea since you will dominate early game. (Not considering the ganks you make)
Hee Hee! Onto Sightstones...Every Lee Sin needs 1. :D It allows for epic plays and jukes which we will talk about in Skill Utilisation Section!
Warmog's Armor isn't that much of a compulsory item...If you feel that Randuin's Omen or Sunfire Cape is more of a better time, by all means get it. It's a situational item.
Zephyr is kind of good on Lee Sin as it gives Attack Speed and extra Attack Damage which kind of works well with your passive (Flurry)
Last Whisper! It gives additional Attack Damage and Armor Pen. Depending on the situation, you may want to rush a tank item, if not just get this item if you are having a good game so far.

Locket is a good item as it gives additional Armor and Health. Its passive gives surrounding teammates a bsae shield amount + 10x your current level. It's a really good item to have because when you engage onto either an ADC or an APC you may get into dangerous situations which requires this item to keep you alive.

Always pump Q as it has the most Damage Output early on.

This skill should be taken at level 3 and should be held on until late game.

On to his Tempest/Cripple skill... It is a really good jungle clearing skill so you can consider to take this at level 1.

This skill as with all Ultimates, should be taken at Levels 6,11 and 16.

Flash should be taken for Lee Sin just in case you get into situations where you have no Sightstone charges left or your Safeguard is on cooldown.

Hmm... Not much explanation here, since virtually almost every jungler should have this skill either to secure Dragon or Baron.

Pros

High Mobility
Has Many Counter Jungling Mechanics
Great Ganks Once He Reaches Level 6

Cons

Requires Time To Get Used To Him
Weak CC Early Game

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Should be the simplest to do. Just place a Ward and Ward Jump to it. Try to Smartcast everything to make it easier for you to place Wards and immediately Ward Jump to it.

through walls

Requires a bit of practice and positioning to achieve this but should be okay with it after awhile.

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One of Lee Sin's most signature combo. Nothing is more gratifying than seeing the enemy's ADC or APC fly straight towards your team. Hard to pull off but it can be a game-changing thing. Try to practice more often. Substituting the Ward-Ward Jump Combo for Flash is also viable.


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This is a really good combo as your Resonating Strike deals 8% of missing health which can be utilised quite well when dragon gets really low then you land your Sonic Wave, quickly Smiting it and again activate your Resonating Strike.

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Another Lee Sin Combo. This time it goes well with a 1 on 1 fight. It's kind of a burst as once again, your Resonating Strike deals percentage of missing health so using it right after you Ulti your enemy can result in a death for the enemy.

Well, this marks the end of my Lee Sin Build. I hope this build helps many people out there who are still learning how to play him well and always remember to EKU!!! :D Peace out.