Q: This is your main Skill.It deals tons of damage at the beginning.You can use it to get faster from place to place in the jungle and also to escape.
W:The Shield is very important for jungling,ganking and safing your teammates.
In the jungle it will give you a boost of lifesteal and armor
When you gank shield a minion or champion and use E,Q or Q,E afterwards.The shield is also very important to save your mates when they are ignited or an op Karthus activates his ult.
E:Nice Aoe skill.Nice movement and attackspeed slow.
R:.I like to use Q (Sonic Wave) on a enemie then the roundhouse kick and Q(resonating strike) afterwards because resonating strike will deal damage of 8% of their missing health.Btw Lee Sin's roundhouse kick is almost stronger than the roundhouse kick of Chuck Norris.

Flash= Op
Smite =Op
Exhaust + Smite also possible (but then i prefer to go for 21/9/0 or 9/21/0 masteries.)

If im on the purple side i like to gank top after my red.
If im on the blue side i will just keep jungling until i see a chance to gank.You should use your red buff for some ganks before it ends.
(I like to steal the big wraith,wolve of the enemie jungler when i see him in the toplane or bottomlane.)
Dont forget to do the 2 Golems because they give you much exp and gold.
Its your job to time the blue,redbuff,dragon,nashor btw: Blue,redbuff spawn 5minute after its death.
Dragon 6 minute after its death.Baron Nashor 7 minute after its death.

Wraiths-->Redbuff-->Golems--> or Golems-->Redbuff if you dont feel save without smite.
Atleast wolves and bluebuff.And blabla...

Shield always your ap or ad carry.Kick champions like Wukong,Amumu,Galio,Katarina away before they can ult your whole team.Try to E 3-5 Enemies and use Randuins (if avaiable)at the same time.If you see that nobody of your team focus the ad,ap carry then tell it to them and use pings before you engage!!.

Pros:
-Very good escape abilities.
-Strong in early game
-very good counterjungler
Cons:
-Hes a blind monk
-no stun skills