So, there are many guides out there for Irelia and I'm going to have a problem with matching up to them.
this being my first guide I'm sure there will be many problems and many things that I could change, any response that could help this will be great!
but if you guys like this guide be sure to up-vote it and give it as much recognition as possible!

The first time I used her I couldn't stand her, I was too much of an aggressive player with always went too deep into the fight where the opponent would take advantage of that, but I gave Irelia another chane when I hit level 30, and I loved her.
She is great to play and can be a good tussle up top from many other top lanes, but she wins majority of time on Champion Select for me.

With Irelia being the strong top lane that she is, farms well and can pretty much put up a battle against any opposition.
She should be the first choice for many people who are looking to start in the top lane.

for now I will publish the guide as it is, but I am currently working on the rest, it will be up within the next week.

good-luck guys!

With the introduction of the new items within the S3 patch.
I have decided that there needed to be a new build updated with these items incorporated into it.

Starting Boots and 3x Health Potion is a pretty standard start for any lane really, but depending on the lane partner I suppose a Doran's Shield could be incorporated as a starting item.

Then for obvious reasons, build into Mercury's Treads for the CC reduction.

Then there is the Phage, pretty standard yet again as you can get that bit of extra health and AD to trade with your partner.

Wit's End, pretty good on Irelia to put out the true damage on Hiten Style and that little bit more of Magic Resist doesn't hurt anyone! pretty standard item yet again.

Then build into the Trinity Force ("Tons of Damage") for yet another bunch of attack speed also with the Passive on the Sheen that is incorporated into this can help you trade more in a fight with your lane partner.

Guardian Angel, nuff said.

And here comes the new item, Zephyr, very good on Irelia because of yet again, another bunch of attack speed and CC reduction, which with Irelia, you wont be out of a fight for long with this.

Then of course, Randuin's Omen, goes without saying, one of the most useful actives in the game, can change a fight if activated at the right time and efficiently to ensure your team gets the ace.

Now, there are many many disputes on which Ability you should begin with as it always revolves around Bladesurge and Equilibrium Strike.

I have always started with Bladesurge as under the turrets, it's easy to last hit with if you are pushed. but then you could also begin with Equilibrium Strike for a level 1 gank if the jungler does so.

When laning with Irelia it is almost necessary to max Hiten Style first, as obviously the damage output will be greatly in your favour in a 1v1. Then max Equilibrium Strike second, for the slow/stun whilst trading with your partner. then Bladesurge to close down those gaps when they are trying to escape.

When engaging on an enemy, Open up the attack with Bladesurge into Equilibrium Strike to initiate the stun/slow, and activate Hiten Style to deal hurt with the help of Transcendent Blades.
you should without a doubt come out of this fight with a kill, or at least smashing them down to low health.

Summoner Spells are a key addition to Irelia as there are many combos that can go well with her.
but the Summoner's I have chosen are Ghost and Ignite.

The reasoning behind these are yet again, to close gaps.
We all know how frustrating it is when an enemy gets away on the lowest HP possible, and we always curse or accuse them of luck.
so with Ghost you can just close them down and Bladesurge onto them.
Kill secured.
or you could simply Ghost and then Ignite.

Other useful spells:

Ghost and Teleport

Flash and Ignite

Flash and Teleport for them global ganks.

Pros:
[*] Strong force in a trade off
[*] Can close down enemies quickly
[*] Easily snowballed
[*] Easy to farm with

Cons:
[*] Can be shut down easily early game
[*] Not really any escapes if no creeps are around
[*] Countered easily
[*] Teemo.