Laning Phase:

If the odds are not in your favour stay passive and farm till 6 but always respond to trades
If you got the advantage start trades against your opponent anytime, move in for the kill if you get the opportunity.

AFTER 6:

Hit a minion 2 times open your w and hit the third strike on your opponent.Simple right?
After harrasing enough this way, you can engage with your stun and kill your opponent.

Teamfights:

Wait for your team to engage then jump on the enemy adc, stun and use ruined kings active and keep on hitting he will die in 3-4 seconds max after that go for their apc and do the same easy win.

*** Always remember you can jump to wards so you can put down your trinket and just q to it (This is only good for escaping unless you need to get closer for a ruined king/omen active)

*** Dont be afraid to fight when you have stacks in your passive

*** If the enemy gives you a attackspeed DEBUFF, disengage you cant fight well withouth attack speed

***IMPORTANT***
Jax needs to stick to his targets and have high as in order to be fully effective. debuffs that decrease your attackspeed and movespeed are your biggest enemys.Try your best to avoid them!!

Have fun playing Jax!