Start by placing your initial portal right next to you, while placing your secondary portal within range of your enemy (without moving).
Step onto portal and travel to secondary portal.
Cast Inca on your target and then (you can choose whether or not you want to exalt) follow up with 3 Bursts.
This leaves you with 1mp to either remain were you are, or return to the initial portal!
That's typically what I had in mind (I'm sure you assumed I meant casting both portals and then moving both to the target to Inca and retreat to attack from portals).