Most people underestimate lee sins passive which gives you a lot more dps in jg and against champs. Once you cast an ability wait for 2 auto attacks to recast or cast another one. The attack speed gives you a lot more dps and can decrease health loss in jg and lane. Also when you use your ultimate u can hit them once while their flying.

If u place a ward you can hop to it with your w ability. This is called ward hopping. his can set you up for very good plays or insecs(which I will explain in a future chapter). If yo hit a q on an enemy veigar and he puts up his stun circle to block you, you can ward hop to the side or over a wall and reactivate your q to get around.

Your ultimate is a crucial component in your ability roster. This can change a game and shut down enemy carries. If u ward hop behind someone and kick them towards your team, that is an insec and can turn the tables of the game. Also you may want to flash behind enemies and kick them back, which does work but there is a faster option. If u kick them you have a 0.5 sec opening to flash behind them and the ult mechanic will kick them behind you. If you have troubles understanding this just go on youtube and search "Lee sin kick flash mechanics".

He is a great jgler beacause he is super mobile and has a lot of early game damage. He is very vulnerable to cc though, and that is the one thing that should keep you from going 12 and 0.