Hi I use this Soraka build in many ranked games and I find it very effective. With a proper lane partner you should have no trouble dominating your enemy!

I use ap per lvl seals and marks to help give your lane partner a nice boost of health throughout the duration of the laning phase, and cdr glyphs to spam your moves early game for a big advantage. Too finish it off I get flat ap runes for quints to boost up my early game heal.

I put one mastery in the defensive to boost up my heal. Then down the utility for cdr movement speed etc. Spamming heals and you peak at 40% cdr.

Flash and CV are viable in coordinated teams. However, In solo q i prefer heal over CV.

You want to lane with a range carry so leveling infuse will help your carry always have mana for spamming moves.

Items i start fairy charm and wards, so you can buy wards for the early jungle ganks!

Pros-
global heal
great babysitter
doesnt need much items
has a silence!

Cons-
terribly squishy
gets focused
not as effective with a non mana lane partner

Your two most strongest lane partners are:
Kog-Maw and Caitlyn
these two use alot of mana and that is were you come in handy.
with your cdr glyphs you should have no problem annihilating your oppenents.