My rotation is very similar to an arcane mage. I use lightning strike 3 times to get the increased mana regen then use force lightning. then affliction. when u get chain lightning throw that in there when the instant cast procs. so basically i do the following
ls x 3 , fl x 1 , aff x 1 , ls x 2 , fl x 1 , aff x 1, repeat. with chain lighting when it procs and shock when they are close to death.