Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
When the champion spotlight came out on Irelia everyone thought she would be an amazing jungler, but I'm here now to prove that she is super op laning too. Now with all the champions who can jungle now odds are your team will have one too. DO NOT BE THAT JUNGLER!!! Now I've won over 700 games now and about 30 on Irelia and haven't yet lost one with her. Now it isn't necessary for you to be solo lane but it makes you level faster, and if the other team also has a jungler odds are you'll both be soloing top. Now early game you'll have a bit of trouble because you don't have much range at all and virtually no lifesteal. So naturally you will want to play it safe until you get to level 6. Once you get your ult you can try and jump the enemy champ and depending on their skill and squishyness you've got a very high chance to kill them quickly.
Mid to Late Game
Okay by now you should have at least a few kills. A fed Irelia is a huge threat meaning that the opposing team will start to try and target you first now if you're playing correctly. Now early on you may have died a few times but the important thing to remember is that carry champs can easily come back from an early game deficit. I saw an Irelia stack attack damage once and I destroyed her because when you get your Hiten style leveled up all you need is attack speed. That's why starks is such a great item for her. Now after you get trinity you should be fast enough to catch any champ meaning that you can kill anyone trying to run from you. The bloodrazer is overkill for attack speed but it means maximum damage to tanks when you use Hiten style. Naturally you want to try and target the enemy team carry first but if you can't blow up a squishy then quickly chop down a tank afterwards. This is why Irelia is so good in games; she can destroy squishy champs and tanks alike.
How to use the skills you've been given
Okay on to how to use your attacks. Your Q attack burns though mana early game so I don't use it as much as some people would, I use it more to push the enemy champs off my tower if I'm solo laning. But as you level up your Q the CD gets shorter meaning that even if you don't kill a minion with it you should be able to use it again very shortly which makes it super helpful in killing opposing champs. Okay on to your main source of dps, your W attack. This attack gives you health return as you attack things but isn't limited to just lifesteal, meaning it gives you health back as you attack towers and barracks also. But the main thing about it is that it offers 75 true damage during the duration giving you the chance to eat through beefy tanks. Now on to the tricky ability your E attack. I say it's tricky but once you get the hang of how to use it this attack can completely turn a lopsided battle. If you have a higher health percentage than your opponent this attack counts as a slow giving you a chance to chase them, but more importantly if your opponent has a higher health percentage than you do they are stunned for the time. Now when you first start to give Irelia a try this attack will give you some difficulty judging the health percentages of your opponents and comparing it to your own in a split second. Don't let this get you down, slows are important too. It's easist if you're at low health by your tower and they dive on you, that way it's a guaranteed stun with the tower and yourself hitting them; and usually you will win this fight. Now your ultimate or R attack will be used more for getting health back or killing minion waves than sniping kills with my build. But if you use it to shoot through the minions while the enemy champs are attacking you, not only do you gain health back but it gives you time to turn around and kill that player. Even at rank 3 it's not so much a killer ability as just a saving one, so when you use it try and aim at the most enemy's so you get the most heath returned.
Well that about sums it up, just remember if you start to die a few times early game it's okay because once you get a little more health with trinity you can live longer and dominate games. Irelia doesn't rely on teammate coordination as much as other champs but it's always nice to play with your friends the first few times you play her so they can help you out.
Thanks for taking the time to read all this and if you have any questions or comments please leave the below. I look forward to seeing you in the field of battle, just remember that just because Irelia is underplayed doesn't mean she's not good.