Hi, this is my first guide on Mobafire so don't hate on me too much. :)
If you disagree with me or just don't like my build, I'm open to suggestions and constructive criticism.

Well, currently, my favorite champion is Irelia, and I've been playing her for a bit.
So I just wanted to share some stuff on how I play Irelia.
I'm not guaranteeing that you'll win every time, because, to be honest, things happen that throw off your game. (i.e. leavers/afks, just a bad day, rage, etc.)
Let's get to it shall we?

Pros:

Farms well
Has some burst
Tanky
CC reduction
Has a stun/slow
Great solo top
Great chaser

Cons:

Harassed by range
No damage early game
I can't think of any more...

I like armor pen marks. I think this is definitely a must for any non-ap dps champion.

Armor seals. Helps with the early game, and early game is very important. Damage reduction is always nice to have. Plus, Irelia already has a high base armor stat which makes this attractive.

Magic Resist glyphs. Once again, early game benefits, damage reduction blah blah blah.

I've looked at some different guides, and I see that a lot of people prefer the armor pen quints to dish out the damage, but I prefer having a bit more survivablity early game and I roll with the health quints. It's nice to have when you're solo top, or even better when you're duo laning.

9x greater mark of desolation Armor Pen marks.
9x Greater Seal of Armor Armor seals.
9x Greater Glyph of Magic Resist Magic Resist glyphs.
3x Greater Quintessence of Health Health quints.

Ah, the masteries.
Lots of debate and stuff, but once again, preference is the key here.

I use the 0/9/21 setup.

The 9 in defensive masteries helps with early game, and the health regen is a beautiful thing to have when you're laning. With health regen, unless you're super aggressive or get unlucky, you never have to leave the lane.

Then the 21 in utility really shines. More regen, experience, gold what's not to like?
Longer buff duration is nice, reduced summoner cds is very nice.

The offensive tree in my opinion doesn't offer too much to my playstyle, because Irelia isn't the dish out the damage and win champion, though she does have burst potential.

should always be a spell.
It can be used offensively or defensively. A great tool to have. Don't leave home without it.

Now depending on what the team has, you want to benefit the team.
You'll see a lot of people with ignites, so most of the time I roll with .

But if no one on your team has an ignite, then don't be afraid to take the .
It doesn't hurt to have a little kill insurance, or a counter to enemy life stealing champs.

transcendant blades > > >

To start off the game I almost always start off with .
It's a great farming tool, but since it costs mana, don't spam it.
Oh and did I mention it hurts too?

, I love this move.
It does a decent amount of damage, and it slows or stuns.
What's not to love? Max this first.

, true damage is always a plus. The passive also adds to your lane staying power.
But I don't find it THAT useful other than lane staying, so we'll max this last.

transcendant blades, another great farming tool. Biggest minion wave you've ever seen in your life?
No problem, hit them with your ult, oh you just got piles of gold!
Oh and if that pesky ezreal arcane shifts away with 20 hp? Use your ult. You win.
Don't underestimate the range and damage of Irelia's ult. It hurts.

When engaging, I use to initiate, the target, then hit my . your ult is negligible in team fights. I use it more to poke and harass before the team fight.
Take note that the ult heals you. If you're low on health in a fight and you're running but there's a hug minion wave? Ult them as you run. HP gain is always nice.

Items. The best part of the game, well, the second best part, after winning. >:)

I didn't put any items after Triforce on the quickview because, you should never build the same thing every single game. It's all situational, but that's common knowledge. (It's amazing to see how many people don't know it, and not only that...)

Anyways, so starting out, I almost always go with a and a . The lane staying power of the regrowth is just too beautiful, but if you know that you're going to be against a heavy ad lane, then a and 5x is great.

Irelia is a great last hitter, so farming should be pretty simple. I usually tend to stay and farm in lane as long as I can, but don't be afraid to go back if you're too low.

My first b back, I usually have enough to finish my philospher's stone and get and maybe a , but it all depends on how much you've farmed.

Then, I go on to finish my mercury treads and my . Last hit like a boss is all I have to say.

Now here comes the fun part...
From what you can tell, look at the items that the other team has, and decide what to build.
If they are heavy ad/as a would probably be a good idea. Heavy ap? .
Now the tricky part is when they have a good mix of both. If it comes to this, I go with a randuins and a banshees. The amazing active on is amazing. makes you laugh excitedly and nervously as you nullify a random ashe arrow when you have 1 hp. But seriously, two great items when you're against a decent mix of ap and ad.

Now the last two items, is preference. If you're still lacking survivability, look at the damage received and decide from there. Do you need magic resist or armor? If you're fine then you can build an offensive item like an . I've never actually tried it, but was a suggestion. I might have to try it out, but usually is the offensive item I get.

Now what to do with that philosopher's stone? You could either sell it and build it into whatever you desire, or upgrade it to a . Now, this is assuming you don't need a large amount of survivability. You should be pretty tanky by now, but by all means, if you don't want to die, get a and laugh as they focus you only to come back and stun them.

Once again, after your core build, buy items that counter the other team.

Farming:
I try to stay in lane as long as I can before I blue pill.
But you don't have to risk your life over farming that last little minion.
Last hitting with Q is simple, but overuse can lead to mana issues.

Mid game - Late game:
When you start moving out of your lane to other lanes and pushing.
Team fights will occur and when they do, focus whoever the team agrees on, which usually should be the carry/squishy/heals.
During the fight, Q and E are your best friends, and W being just a friend.
Q in, E the target and hit your W. The outcome depends on your team.

After a team fight, everyone's health will have a portion of health missing.
Unless you're super low, you should be good to farm a bit more, or push.
Irelia excels when she has lower health than her enemies. The stun on e works when your health is lower.
Oh and when you see someone being chased and you're low health dont be afraid to Q in and E the enemy to save your teammate. I've done this many times. Sure it pisses them off, but it feels good when your teammate gets away with 2 hp.

Irelia is a great champ and if played well can be a great asset to the team, almost on the level of carry, but not quite.

Farm is essential to any champ, but Irelia farms with ease, so you should never be under farmed.

That's all I have to say about how I play Irelia. Thanks for reading the guide and I hope you beat some booty in-game with my favorite champ. Have fun!