During my time paying Jax I believe that starting out with the Hunter’s Machete and 5 health pots is the best way to go. after you have saved up some gold buy the Greaves and the Bilgewater Cutlass at the same time this really helps you put out max dps. The cutlass works well to keep enemies near you when running away, teamed with Jax’s stun gankinmg should be a breeze. After the cutlass go into the Phage this will give much needed health for ganks and as always another chance to slow and some damage. From here on out build what ever you need start getting magic resist and armor or if your team is doing well get the Hextech Gunblade.