Quick writeup for ARAM Soraka: designated Warmog's holder.

In patch 14.10 Warmog's was buffed from 750 HP to 1,000 HP.
So Warmog's now only requires 300 extra health for passive to activate.
Usually, you will have enough gold to buy Warmog's and extra HP around level 8.

• 160 HP from 2 scaling HP shards at level 8.
• 150 HP from 1 ruby crystal

That gives 310 HP.

Tear and Presence of Mind is mandatory, otherwise you will be limited by mana after Warmog's comes online.

Soraka can't make use of any Precision path keystones, so Precision will always be the secondary path for Presence of Mind.
((mobafire hasn't updated runes yet))

Resolve Path
Most healing, least damage.

Keystone: Guardian
Row 1: Demolish > Font of Life
Row 2: Bone Plating
Row 3: Revitalize
Font of Life used to be great, but was nerfed on 14.10 and is now very mediocre.

Sorcery Path
Less healing, less shielding, more damage.

Keystone: Aery
Row 1: Nullifying Orb ~ Manaflow Band
Row 2: Transcendence
Row 3: Gathering Storm ~ Scorch

Domination Path
Build acceleration.

Keystone: Dark Harvest
Row 1: Cheap Shot > Taste of Blood
Row 2: Eyeball Collection
Row 3: Treasure Hunter
Treasure Hunter earns more gold by level 8 (when you get Warmog's) than all of the Inspiration path runes combined.