Lulu has seen a fair amount of play recently as an AP carry, but I perfer her in the role of support. She may not be able to win you bottom lane handily as Alistar or Leona, or supply your team with heals as Soraka, Sona, and Taric might, but her handy crowd control and amazing teamfighting capability make her a mid-to-late game support any team should fear.

I play Lulu with a standard support rune set:

9x Greater Marks of Insight
9x Greater Seals of Avarice
9x Greater Glyphs of Warding
3x Greater Quintessences of Avarice

This, along with your masteries and your items, will make sure that you're never hurting for gold for wards and support items.

I run a 0/9/21 mastery page for Lulu, making certain to pick up Summoner's Insight, Greed, Wealth, and Mastermind in Utility.

Start off with a Faerie Charm, Health Potion x3, and Sight Ward x3. Alternatively, get one Sight Ward and one Vision Ward instead of Sight Ward x3. On your first trip back, grab a Philosoper's Stone, Boots, and a Sight Ward or two. Wards are paramount. If you can afford boots, but not wards, get wards instead.


Lulu's core build is Ionian Boots of Lucidity > Philosopher's Stone > Heart of Gold > Sight Ward Remember the ABW principle: Always Be Warding. If you're getting lots of assists and aren't dying, consider an Oracle's Elixer around this point.


Lulu's final build should be centered around one of two directions: aura-based passive support or Help, Pix!/ Glitterlance active support.


FOR AURA SUPPORT: Abyssal Mask, Shurelya's Battlesong, Locket of the Iron Solari, Will of the Ancients, Zeke's Herald.

FOR AGGRESSIVE SUPPORT: Abyssal Mask, Rabadon's Deathcap, Zhonya's Hourglass, Rylai's Crystal Scepter

Either path will work, but regardless which path you go, the ABW principle applies.

Skill order is R>E>W>Q.

Pix, Faerie Companion is a nice little passive that opens up various opportunities for Lulu, including the possibility (very slim possibility) for an AD carry build. For you, though, it simply allows you to harass better and allows Help, Pix! to be just that bit more helpful.

Glitterlance is an effective poke, but as support, it can do a bit too much creep damage than your carry may appreciate. It's strong enough at level one that you can max it last and not harm your progression too much.

Whimsy is an amazing ability that can either give an allied champion movement speed and ability power, or hamper an enemy by turning them into a squirrel/cat/cupcake that cannot autoattack or cast spells and moves at a significant penalty. The scaling is good enough to max reasonably quickly, but not immediately, so max this second.

Help, Pix!, like Whimsy, operates differently depending on whether it is cast on an ally or enemy. On an ally, it grants a shield and gives your ally the benefit of Pix, Faerie Companion. On an enemy, it operates as a strong poke, grants vision, and attaches Pix to the enemy for a while, allowing for some interesting autoattack angles. I max this first for the massive poke and shield scaling.

Wild Growth makes a targeted allied champion HUGE, knocking up nearby enemies and slowing enemies around them to a significant degree. Nothing is scarier than piling on a carry, and then getting knocked up and slowed while a Lulu's team tears you apart in the tumult. Max this whenever possible.

Clairvoyance provides vision of key objectives, and lets you check bushes from safety. I always carry this spell on any support.

Flash is a strong spell on any champion, regardless of role, but in Lulu's case, it can be used to catch up to allies just quick enough to pop your entire spell selection on an allied champion in trouble.

FAVORABLE MATCHUPS:

Alistar: Is he going in for his big Headbutt/ Pulverize combo? Whimsy him right in his bull face. Crisis averted.


UNFAVORABLE MATCHUPS:

Sivir: Spell Shield can block Glitterlance and Whimsy fairly easily, and gives Sivir mana to boot. Not so good.

Soraka: Soraka's insane sustain with Astral Blessing will give you a hard time, and Consecration will make your early-game poke reasonably weaker. Your best bet is to rush out Abyssal Mask and Morello's Evil Tome and hope for better luck in teamfights.

Pros:

Great poke
Amazing teamfight capability
Awesome debuffs


Cons:

Negligible sustain in lane
Mana problems until later in a match