this build works very well for me...your playstyle may vary
Try a 9/0/21 build with a full page of CD runes( -14.82)
Meki Pendant X2 Heal Pots(I have had some success with both lane mates getting Mana Manip--but MM doesnt build to anything useful later on)
Pendant to Codex
Chalice ONLY if your having mana issues, or someone on your team is hoggin' Golem Buff(rude) Sell this later on when mana isnt an issue
Codex to Deathfire Grasp(Extremely important for CD redux and nuking down someone stacking health)
Abyssal Scepter in any order you choose
Void Staff in any order you choose
if the game goes that long or your just wrecking peoples faces in,
another Zhonyas or Archangels staff
Best lane partner by far: Blitzcrank...pull to Rune Prison etc is GG
Anyone else with a lengthy ranged disable is awesome here as well (Sion, Taric, Fiddle)
I start with SF, then to RP, then to OL...Then i build SF for harrass, then RP, then DP..etc...SF is going to be your main harass and farm and is key to killing someone early...learn to bounce! I have also found this skill to be fooking buggy as hell, often giving no bounce even when theres clearly other targets...ive also seen insane long distance bounces. One time i killed a retreating Sivir that had completely run past her own turret and i was outside of its range.../shrug.
My attack order is USUALLY:
Desperate Power, Rune Prison, Deathfire Grasp, SpellFlux, Overload, Flash to safety, circle and kite, Rune Prison, whatever else you have up.
Always stay behind your tanks and always let them iniatiate.....never roam on your own, your **** squishy~! Your target priority should be anyone who you can reach who has the lowest hps..only target tanks if there are no other targets....You need to kill someone quick off the bat and make sure your team has the upper hand while your spells are cycling.