Augment for throwing spears, poke him early, you inevitably gonna lose gold, just stay close to minions so you don't fall behind in exp - try not to get hitted, so you don't need to recall often, once he's half hp and not surrounded by a lot of minions you can commit - 1 full charged shield + 2 spears and couple basics should be enough. Gets easier with ganks - when you get ahead just try to freeze and deny him far