What this guide isn't:
-Complete how to play on Soraka (it will show you the best direction and most likely way things will go down).
-Situational breakdown (its literally impossible to cover the situational modes of Soraka as there as so many).
-Guarantee for success (some fail, some triumph, i wont tell you that if you use my methods and builds you will automatically be crowned champion of Runeterra, but there is a good chance).
-This build is purely intended to rip off fast heals. You will be casting powerful heals every ~3 seconds. Following this build, your assist number should be scary.
-College grade essay on how to play a champion. Hell, you can just use the build up there and be on your way, the stuff below is just coffeehouse chatter.

Pros:
-Heal
-Heal some more
-Give mana
-Support the entire team

Cons:
-Squishy
-If you miss click, it could cost you the game
-VERY situational
-No to barley any dps done

DO NOT underestimate Soraka!! She is EXTREMELY powerful and can carry the carries! Those squishes that are taking all the damage can be rescued, and those vital turrets can be saved! Soraka is, in my opinion, the STRONGEST support class to date!

By the way, i won't bombard you with pictures, icons, and other ****. Here is one image to prove that, at least, it actually did something. That is the last image out of me, the rest are small icons that are forced by the system in order to show a description of an item/spell/person.
(Surrender at 20:00)

AP runes all the way, all you need is AP. The items handle your CD, so around Mid-Game you should have capped to the CD and be on your way to 6 second powerful heals. Stack AP runes.

The masteries go without saying. Basic utility package with cooldown reduction, mana pool increase, experience gain, and movement speed. If you believe you will be able to handle constant infuse, then ditch the mana for some reduced time spending since squishes usually die in team battles late game and you want to get back in the fight ASAP.

You may say "OMG FORTIFY AND TELEPORT WTF USELESS!!!!!!!!!!" but you don't realize how damn important they are. As a support, it is your job to maintain the integrity of the team. If you see a lane in trouble, pop your teleport over and heal the damaged mates. If a lane is being pushed but no one is tending to it, toss the fortify and pop over.
These spells can not be debated. Fortify and Teleport are the absolute must of any support. Your healing and mana infusing is enough to make up for Clarity and Heal.
However, if you must, grab Exhaust instead of Fortify in order to slow an enemy's advance.

Cooldown reduction, health, ability power, and mana. All necessary items. If you are seeing that your team is not very squishy, ditch the Morello's Evil Tome for some extra AP, such as the Zhonya's Hourglass. The hourglass is also very useful, however i find it not to be extremely important to me therefore do not include it in the build.
The reason for the Mana Manipulator at level 1 is because your infuse will be not only be available at level 2 but it will also be not very strong.

Many people tend to get Infuse first because it seems like the plausible option - deal damage and give/get mana. However, many people like to go for first blood. If, for example, you have a very tanky Jarvan IV, you want to toss your Astral Blessing at him as much as you can to keep him going and killing.
Your casting sequence is very, VERY situational. It gets no more situational then these spells, and i can not express how timing is crucial.
Your best bet is to cast Astral Blessing on the person taking most damage, and then either Infuse yourself if you are low on mana, a friend if they are low on mana, or an enemy to deal some damage and silence them. Silencing a Katarina immediately after she dives into the crowd could prevent her from casting Death Lotus and ending the fight.
Starcall is pretty useless, but in team fights you should try to cast it as much as possible if you are close to the enemy in order to lower magic resist and deal some damage. Remember, your role is SUPPORT and HEAL, not OFFENSE and DPS.

Just as a reminder, i added this section.

NO TEAMWORK = YOU ARE DEAD AND YOU LOSE. PERIOD.

Soraka (and any other support for that matter) relies HEAVILY on the team, and it HEAVILY relies on you. Teamwork must be at its best, or failure is in the near 20 minute future. If no one guards you and coordinates with you, the team will lose. Its worse then having an AFK person, because everyone will be in the ordeal of confusion about what you are doing. Soraka has the highest ranked winning ratio, and that is because Soraka is played with a hand picked team. When i play her on Normal Solo/Solo, my success rate is 50/50.
However, when i hand pick my teammates, my success rate is a staggering 95/5. If your communication is up to par and your mates aren't a bunch of dimwits, you shall have some IP and wins in your bank.

In early game, your heals are weak and you are very squishy. The heals are enough to handle harassments (like Olaf's Undertow) but not full head combat.
Your Infuse will give considerable mana, and if casted on yourself, the amount is double. You may cast it on a mana user to give him the base and it will also grant you the base value.

After level 8, you are quite ready to be considered an awesome healer. If laning phase is still happening, attempt to set up a gank. If you have a jungler, this should be completely easy and success should be netted. For example, have your tank and you hide in one side of the brush, with the jungler/ganker in the adjacent brush if possible. Immediately before the tank initiates, post up your Astral Blessing on him and silence the closest DPS dealer with your Infuse. The armor buff from Astral Blessing can be the deciding factor between win and lose.

If the enemy hasn't surrendered by now, prepare for a heck of a W spamming time. Late game is impossible to describe, and you are extremely situational at this point. Attempt to cast your Wish during team fights when heal on 2+ people is halved, and try to stick to the back of the pack behind all your people in order to stay away from damage. Most likely, they will attempt to target you; however, many people do not realize Soraka's healing power and simply go for the usual Caitlyn, Ryze, etc.

Watch the team's heal bars, mana bars, and location. Timing and sequencing is crucial, and everything Soraka does is situational.

Thank you for reading!

If you need help or any questions/comments, DO NOT be afraid to leave some words below! I am ALWAYS looking around and (as far as im concerned) will play LoL until it's end. Please, by all means, ask! I will 99.99% of the time respond.
My portfolio can be found by clicking here.

Prepare to play the best supporter in the game!