Get good at poking early game in your ranged stance, but learn to swap between stances and effectively use all of his skills in a stance before switching back again. Train yourself to switch often and effectively for the situations that come up. Switching gives you extra armor and extra damage, and the the W on both stances after switching can add a huge amount of damage and turn a fight quite easily.

I'm still up in the air about the greater quintessences. Movement speed, lifesteal, or attack damage could be good here as well. I like the scaling runes since you're just poking at the beginning anyhow. The scaling runes make your late game that much stronger in the long run.

The last 5 items are situational, but I do recommend having health on it.