Soraka

Support

I Lend My Aid

Heals, heals, and more heals.

Sorcery

Empowered abilities and resource manipulation

Summon Aery

Your attacks and abilities send Aery to a target, damaging or shielding allies.
Manaflow Band

Hitting enemy champions with a spell grants maximum mana.

After reaching 250 mana, Manaflow Band restores 1% of your missing mana every 5 seconds.
Celerity

Gain 3% extra MS. Gain extra AP or AD, based on your bonus MS, Adaptive.
Scorch

Your first ability hit every 20s burns champions.

Resolve

+65 health and +10 AP or +6 AD, adaptive

Revitalize

Heals and shields are 5% stronger and increased by an additional 10% on targets below 40% health.
Font of Life

Impairing the movement of an enemy champion marks them. Your allies heal when attacking champion's you've marked.

WhySummon Aery

Summon Aery is a great option for Soraka both offensively (with autos and [Q]) and defensively (with [W]).

WhyManaflow Band

Manaflow Band is a great option here for Soraka because you're going to want to play aggressively in lane early spamming [Q].

WhyCelerity

Celerity on Soraka allows you to position yourself safely in teamfights and skirmishes so that you're able to continue pumping out heals.

As a added benefit, when your passive kicks in and you get the Bonus Movement Speed towards low allies, Celerity will grant a bit more extra AP to empower those heals.

WhyScorch

Scorch allows you to dominate the lane phase if you're able to consistently land your [Q].

WhyRevitalize

Because you're going to be healing so much over the course of the game, Revitalize gets fantastic value, especially if the target is low health.

WhyFont of Life

Font of Life doesn't seem like an obvious choice but if you can land your [Q] regularly it synergies well with your itemization and Revitalize.