You need to get used to her, at first I really sucked, but then I ended up dying just 1 or 3 times. I almost never make use of her passive, so its harder to get kills but you get a lot of assists and ...you stay alive!!
I was thinking about sticking the ball to nunu/kat/fiddle and ulting to make their team really suffer their ults. Never actually did it, but it sounds good 
You can also E some ally in trouble and W to get him out safely.
I get RoA , Ionian boots, Rabadons, Zonias, and then maybe Void or GA depending on the game. Never actually got longer than that.
I´m thinking about trying Guinsoo´s on her too, it actually gives like 90 AP with the 8 stacks. And allows you to use the passive efficiently. only tried it on bots though.