Hello all! Since the release of Diana I've been playing her constantly and this is my personal build that contains: Sustain, damage, and survivability. I mainly rush chalice to begin with due to her mana problems throughout the game and it keeps you in lane and afloat through the whole game eventually. Hope you get good results out of this, enjoy!

(Note, I will continue working on this guide in time, for the meantime I'm just simply getting the item build out there.)

Pros: Cons:

Great damage throughout the entire game Bad mana sustain without blue.
(hence Athene's)
Akali like ultimate that has short cooldown
(even shorter if you can land your Q)
Can't think of anything else at the
moment.
Pretty tanky to begin with.

Can disrupt entire team fights with her e.

Meki Pendant early as first item to sustain your first say... 5-10 mins in lane. Rush it into Chalice of Harmony, holding out on boots until after buying the chalice. Turn them into Sorc Boots to increase your damage by penetrating their MR more. Rylai's for health and that great slow we all know and love. Lich Bane to be able to do burst damage whenever you need it and in between cool downs. Revolver into gunblade for auto life steal and magic vamp. For your last item I suggest Frozen Heart if you're having trouble with those pesky ad carries or bruisers; since you get MR out of Athene's anyhow. Or if it's the other way around you could build an Abyssal Scepter for more AP & MR (and a great passive).