The Praised Healer

The Praised Healer build is a build for Soraka to put her potential to good use, which of course is healing. Soraka is the (arguably) greatest healer of all champions in LoL so far. She has two good hitpoints healing abilities, and one mana healing ability. Unfortunately her astral blessing has a quite long cooldown, thus i have taken forth this build to improve that con. But also make sure she gets a good amount of ability power too.

Pros and Cons

Pros

Excellent healer
Nice supporter
Immediate silencer
One of the best at staying in lane
Can heal from far away (ulti), also grants one assist if enemy is killed in the next ten seconds after using her ulti
Can get assists easily (helps for mejai's)
Free harass
Good survivor

Cons

Squishy
Deals close to no damage mid/late game
Delicious target for enemies
slow farmer
no champion for the kill lovers

Summoner Spells

Spells to Get

Heal: You are a healer, remember? This will be good in teamfights or when escaping, to stay alive that is. However, it should never be used instead of an astral blessing when out of harm's way. It's cooldown is way too long, even with the reduced duration from masteries. Unfortunately it reduces future incoming healing receieved by those who attained it for a short duration. Use it as a last resort.
Clarity: You will fill up your own mana pretty quickly with infuse, but for other champions you might find it will restore almost no mana at all. It depends on the mana pool. Therefore this spell will be so useful to help your team. However, if you play with many no mana users like Kennen , another spell would be prefered.
Rally: I've never used it, but I think it would be an awesome spell for anyone to use in teamfights. This is meant to boost dps allies attacks. This is just an idea, I haven't used it, but I'm no experienced Rally user so...
Ghost: Good spell to escape, chase down(only when you're certain to kill) and get to allies to start doing what you do best, heal!
Clairvoyance: Clairvoyance is a good map control spell, and since many other champions can't give up another spell for this one, you have that possibility. Exchanging heal for it could do. If you know how to use it, give it a try.

There are some other spells that are also good, but those work with mostly any other champion. So I'm not going to list them here.

Spells to Avoid

Cleanse: If targeted, You'll probably be dead anyway, even with the use of this spell. Plus, you aren't supposed to let the enemies get so close to you. Besides, if insisting on survivability, Ghost or Flash is better. If you find that the opposite team have bulked up on cc's you might want to substitute an item slot with a Quicksilver Sash , which is by far better than cleanse.
Exhaust: Not worth it, you're no fighter. And if you consider it for teamfights, leave it. Others will take it, I assure you.
Teleport: A good spell to help a poor allied turret under attack, or to get to your allies, who are pushing other turrets. I see why many people want this. I do too, but not with Soraka. Why? well because, if you teleport to a turret that is under attack in mid/late game, you might just get killed yourself. And if you want to quickly get to allies that are stuck in teamfights, there must be a nearby turret or minion, if not... it's wasted. You won't need to get back to lane so often either, so use this slot for something else.

There are, of course, other spells that aren't very useful for her, so why should I tell you the obvious reasons you already are aware of?

Ability Sequence

The order of lvling Infuse or Astral Blessing may vary between players. I Like to lvl Infuse first because of greater mana heal and for harass purpose. However, the heals won't be as strong that way, so the astral blessing may be lvled foremost instead, for greater heals. But keep in mind that you'll be more mana hungry that way.

Runes

Nothing strange there, is it? Cooldown reduction and some ap for faster and greater healing. Plus a little health for yourself, to save your sorry ***. What many might react upon is why i do not pick flat runes and go by using runes that becomes greater by lvl. Well, solely because per lvl runes give you more value later in game. Where I think Soraka is needed the most. She will probably has to heal 3-4 champions at the same time. not as many early game, so the flat runes aren't the best for her case. She does not need an early kill. It is up to you to decide which runes to go with, however. You do not have to blindly follow this build.

Masteries

Most important here is cooldown reduction and the 15% reduced summoner spell cooldown is also useful. one slot in defense for shorter cooldown on heal instead of the extra 15% in magic penetration. Simply because Soraka doesn't do much damage with her spells anyway.

Items

And finally the items. What the hell was I thinking when getting armor for her you might ask? and why those shoes? Is he stupid? Not really, I will explain everything.

Mejai's Soulstealer: This is the source of your ability power. You won't get many kills, but certainly many assists, if you play efficiently and stay out of the fury of battle. It will take some time but will build up quite nicely. And upon reaching 20 stacks, 160 ability power and 15% reduced cooldown. Sweet!
Boots of Mobility: Simply to get from place to place faster, keep up with your team, and run away when realizing the enemies attention is being directed at you. Also, healing does not count as going into battle. So you will still have your extra boost after healing someone, Thus hard to pursue.
Spirit Visage: A really good item for Soraka, and quite cheap too. cooldown reduction, magic resistance and increased healing to herself! Also a good idea to encourage your teammates to get a copy of this one too. later on your astral blessing should heal yourself for half the ammount of maximum hp, even without 20 stacks in Mejai's with this item.
Soul Shroud: Soul Shroud is a great item for Soraka. It has a very good aura that also helps you alot. The extra health is a good, but most importantly the cdr is neat. Stacking with runes and masteries leave you close to 30% cdr. The maximum cdr obtainable is 40%, so if you acquire 20 stacks in Mejai's you've got those 40%. And that is really helpful.
Aegis of the Legion: Good all around defense. The aura is the most important part though. The true purpose of the item. You are a support after all, so you better fulfill that role (Can be replaced with Soul Shroud).
Zhonya's Hourglass: This is where a new ability power item will be considered. There are two options, Zhonya's Hourglass or Rabadon's Deathcap. Take Zhonya's if you need more survivability and if you care for those precious stacks on the Mejai. If being targeted in fights you can always activate that active to survive at least a few more seconds. Might save your life.
Rabadon's Deathcap: Rabadon's Deathcap is For pure ability power. Compared in ability power this item surpasses Mejai's Soulstealer. If you feel like you're feeling safe on the battlefield you can get this before Zhonya's Hourglass. After you've gotten all items, get elixir's too boost yourself. Also oracle's elixir for sneaky bastards and mushrooms.

Gameplay

Early game

Start out with an amplifying Tome to boost heals. It's better than Doran's Ring since it's upgraded into Mejai's soulstealer. You will more likely be able to get the boots of mobility at the same time when purchasing Mejai's.

When in lane do not get too close to your enemies, stay at a safe distance and harass some with auto attacks and infuse. If playing with mana hungry allies, like Veigar , use your infuse on them very often. Try to do some proper harassing early so the enemy will have to stay defensive and you'll hopefully get down the first turret averagely fast. Upon reaching level 6, check if your teammates on other lanes are in need of health. If so use your ulti, or if you want to save it for pinches, don't.

Mid game

If the first turret is destroyed head to other champs to heal. now you should get mejai's and boots of mobility if you haven't already. The true challenge starts here. Now you've got to babysit several champions. Get assists and build yourself towards those desirable 20 stacks. Don't wander about alone, and go only alone if to defend turrets, but Take care if enemy champions are nearby.

Late game

The same as with mid game. Stay back in teamfights, cover their backs when allies are engaging, and heal away. Only use wish when necessary. Use wish to save lifes. Now you need to use infuse on yourself alot too, Because your heals will be spammed and drain much mana. use clarity for allies foremost. that way they don't have to recall after every battle because they ran out of mana and are useless without. Lux and Kassadin are some examples.

Combat Tips and Tricks

If you are facing an enemy alone or together with your laning mate in beginning of game, there are ways for Soraka to deal damage and be useful other than as a support. Her Starcall spell is an underastimated spell that actually helps in various ways. It's mostly considered a good farming tool, and it is, yes. But, it can be used in fights, not only to deal some extra damage except for your auto attacks but will also reduce magic resistance for each starcall. This makes your teammates spells even more powerful and also your own infuse is boosted. An idea is too keep spamming starcalls and finish it off with an infuse if the target is running away or either at the brink of death, for a nice kill.

Few take in mind the magic resistance reducing when confronting Soraka and thus laugh at the low amount of damage she deals, until she pulls off her infuse that is. The magic resistance reduction stack up to 20 times. So use her Infuse in the end of a battle. However it's not a great deal of damage output source, but still something to help in battles. Makes you feel that much more useful;)

*Her starcall spell has been nerfed recently and has a shorter range than before. Use it when you can but don't get in over your head. Better is to silence an enemy champ at a good time.

Summary

So, I guess I've taken up the most important details. If anyone find something missing, tell me so. Criticism is always welcome. If you like the build and aren't too lazy to thumb up, please do so:)
This is my first build, so if you think it's bad... then just thumb it downxD