Hello and welcome to my Lulu support guide!
I will focus on carrying your carry, helping in teamfights and map awareness.
So if you are looking to be a useful Lulu this guide may help you out!
Lulu is a really fun champ to play and she can be really helpful without stacking a lot of AP and even then get these kills on champions that are running away with low health or even better, kill these that are chasing you!
She's got a lot of synergy wit other champions and can cast great and devastating combos.
With a little practice it will be really hard to kill someone in your team with you around.
I'll keep it short and simple for now.
This guide will point out how to:
- have shorter cooldown early game;
- have no mana problems so you can spam spells like there is no tomorrow;
- provide map vision so you gank effectively and never get ganked;
- mid game you will make 1.5 gold pre second


Also, this is my first guide.
This is still work in progress! All bellow "........................." is just a sketch!
Enjoy!

With masteries, I go for 9/0/21, this setup will make you rich and your spells will be on a lower cooldown from early game without cooldown reduction runes.

9 in Offense:
Mental Force : 4 points give you 4 AP, not much, you only really need to unlock second Offense tier;
Sorcery: 4 points for 4% cooldown reduction, this will add up with the 6% you get from Intelligence ;
Arcane Knowledge : 1 point, take this it would be a waste otherwise, it's a nice buff that can hurt.

0 in Defence.

21 in Utility:
Summoner's Insight : 1 point for the extended Clairvoyance is a must.
Expanded Mind : 3 points, bonus mana is good;
Improved Recall : 1 point, this can save your life;
Meditation : 3 points, for this mana regen that will add up with your runes;
Greed : 4 points for nice money flow so you can really afford these Sight Ward's and much more;
Wealth : 2 points for additional Sight Ward and a Health Potion at the very start of the match;
Awareness : 2 points, makes you level a bit faster, this is taken to unlock Intelligence ;
Intelligence : 3 points for 6% cooldown reduction, together with Sorcery this will make it 10%;
Mastermind : 1 point, take this to have your Clairvoyance and Heal ready more often.

Lulu's spells really shine when they are maxed out asap.
I don't see a point in unlocking one spell early only to max it last.
It's a waste of level, this skill will not make much difference in aiding your team and will only make the skill you could have levelled up instead less effective.
This is why I'm not taking any points in Whimsy until I have no other choice.
I'm not saying that this is her worst skill, it's just that the shield from Help, Pix! is really amazing and the damage it deals to enemies together with its awesome utility.
Glitterlance is what will make you shine and when used correctly will make the enemy team drop their jaws, look at your build and wander WTF is going on! Where are your AP items!?

.......................................................... All bellow here is just a sketch!

Max Q first for surprising slow and damage. This will also let you clear minions in no time when needed.
Next max your E, always shield your team mate first! Use it on enemy only when they run away to help your team chase. Using Q will shoot the slowing beam from where Pix is.
Obviously take a point in R whenever you can. Use your ulti in teamfights. Don't even think on using it on yourself unless you are the last one standing.
Throw it on your most surrounded/focused mate.

Take Clearvoyance and use it on pushed lanes without wards if you don't know where enemy jungler is or if someone is missing. This is a must have spell for supporters. Later use it on dragon, baron although you should have it warded.
Take Heal to annoy enemy and keeping your team longer in fights, when used in the right moment it can change everything.

It is you who will need to ward. This is a bigger help then having a lot of AP. You will need to buy wards all the time and get gold to buy more wards. When your team is aware where your opponents are, they stand no chance. Buy 5 wards first, if you have money left buy other items. If you run out of wards and there is no team fight, no dragon or baron, or nothing important you can help with go back and buy wards. If the game is really long buy auras.

In early game you need to support your carry!
DO NOT CREEP STEEL!
DO NOT KILL ENEMY CHAMPIONS!
Let your carry kill them!
YOU DON'T NEED KILLS!
Stay in bushes, damage enemy champs, buff your mate.
In mid game, never ever go farm, always stick close to your team and put wards down so you can see all the area around, make sure you don't get ganked!
You don't need to watch not to kill creeps later on and if you are having a lot of points in Glitterlance, you will kill whole minion waves in one shot. You will be a great pusher!

If you help your team like this, you will most likely win and yes a big part it this victory is you help, REWARDING!

Lulu so far: