Hello Guys. This guide is easy-short-effective. I recommend to all of you.

Jax is a very effective hero when he is in good hands. His abilities are generally buffed from AP and he owns on 1on1. Nearly the best hero to take down the key hero of the enemy. He has got 5 sec CD leap to find the right target on the right time. This ability with right items make you irresistable hunter.

Greater Seal of Evasion - Evasion > all
Greater Quintessence of Evasion - Evasion > all
Greater Glyph of Potency - AP buffs all abilities
Greater Mark of Might - Best buff to dps through marks

My built depends on AP and survival. so 21 point goes for defense. Ardor is so nice.

And also Dodge masteries in defence tree just own other trees.

Item sequence is very important for this hero. During the cooldown of the leap, you NEED SLOW !!! Bilgewater Cutlass/Hextech Gunblade is what you need. So after Ninja Tabi Boots, get it quickly.

After Cutlass getting Sheen will be a good choice. Low price high effect.

After Hextech and Guinso, Lichbane and Nashor's Tooth combo just owns.

My sequence is one of the best for taking down the DPS/CC hero of the enemy. I preferred pure AD and AP items because of the passive skill. With these items granting HP with your passive skill makes you a bad-*** that doesnt die. You cant be taken down so easily. And remember that "SURVIVING JAX OWNS".

If you want to be a killer. Leap strike is the first skill to be fulled. 5 sec CD is a must in fights (1on1, laning, or 5on5).

Dont forget ! You are a melee fighter. YOU HAVE TO STICK ON YOUR TARGET...

On the other hand, just give other points carefully for the best dps.

Exhaust - just for killing and debuff enemy key heroes (like katarina)

Flash - to escape when you are focussed on 5on5 fights / and to kill ofc

Pros:
1- Good killer
2- Hard to kite
3- nice dodge and magic resist abilities against both physical and magical heroes
4- AOE stun
5- Effective all the time
6- Good lane mate
7- nearly best on 1on1

Cons:
1- Focussed
2- Not an easy hero to master
3- Item dependent

Every creep(gold) counts. You have to get your items quick to own. With ulti it is easy time to get the last hit.

Red Buff is very good for you, so dont forget to get it before fights.

In 5on5 fights, aim for the squishy but most effective heroes. You just own them and make them escape from the fight area or let them fall in the battle. And just dont let them go. STICK ON THEM !!! use exhaust here first and if your target escapes with flash, just use your flash afterwards. And BAM he is dead.

Chasing and attacking is very important for you because Ulti's refresh time is so short. SO Dont lose the stack !

In laning, Q+E combo is a good harassing. So use this combo with mana efficiency. Dont waste your mana on tanks. Just aim for the squishy targets or targets with not enough regen.(for example doran's ring starters)

Tip 1 - on 1on1 you are nearly undefeatable if you know the stuff and with the appropriate gear of course.

Tip 2 - Aim for the DPS/CC/Key hero of the enemy. Dont let them go, haunt them until you kill. (This is so important for JAX, because JAX's natural enemies are these heros. In this situation, i take Exhaust and Flash. Trust me in 5on5 fights these skills OWN.

Tip 3 - Try to harrass in the lane all the time. Just use the combo(Q+W). But use mana efficiently of course.

Tip 4 - Dont try to be a hero. Always play guaranteed.

Tip 5 - Hextech is your best friend. use the active skill after you land on the enemy.

Tip 6 - DONT ATTACK TANKS. Just kill the key heros. Tanks are piece of cake after them.

Tip 7 - use the "E" when it is up. It is a lifesaver and also a killer skill.

Tip 8 - you must get the 2 pickaxes in the early-game. Very important because your dps depends on mainly "Q" Skill and its damage come from mainly AD.

Tip 9 - Dont be afraid of other heros. JUST FACE THEM. Stack the ulti, follow the CDs carefully. Q-W-E skills have very low cooldowns so spam them all the time. Melee heroes just cant kill you. Bear that in mind ! for casters you have your ulti giving bonus to magic resistance. YAY ! Range DPS can be pain in the a.. because they generally run away from you and try to kite. Aiming them will be a good choice with the exhaust+hextech.

I will upgrade this guide as i play more with JAX. This is my first guide. I hope you like it guys. Cheers !!!