Hello everyone, my english is maybe not the best because i'm german.
I'll show you my ownn Jax Guide, that i worked out myself.

I Hope you enjoy playing this guide :)

My masteries are very offensive because i dont really lioke playing jax as a tank. I prefer playing him as a "Hybrid Carry"

I take all Ability Power Masteries and most of the aattack damage, because Jax deals most of his damage with his Ulti-Passive.

I start with Boots, because i dont want to waste money for a dorans Item, if you want to take one, it's anyway which of them you take.
The Ninja-Tabis are a necessary Item for Jax. The Dodge Chance is rly nice.

The Guinsoos combined with his Ulti passive gives you full stacked about 1,8 Attack Speed.

The Hextexh-Gunblade is one of my favourite Items ingame. Lifesteal, Spell vamp and Damage.

The Trinity Force is a really nice Items combined with his E-Skill: Jump one Hit and BÄÄÄÄM.

Rylais is nice with his Q-Skill, cause of it's slow, and a big amount of Life and Ability Power.

Finally the Black Cleaver, it has got a nice Passive that reduces the enemies Armor for up to 45, what is really nice, it gives a little Attack-Speed too what is really nice ;)

I really like Jaxs Skills, some Stuns and an epoic damage output.

Just skill like its shown up here, because his dogde chance can save your life in fights 1v3 and you can get 2 or more of them.

All in all this Guide changes Jax into a undeafeatable 1v1 Champ with about 3600 Health, 280 Attackdamage and 250 AP.
ENJOY!