Hi, and welcome to my first build. I'll be talking to you about Ezreal. Ezreal is an extremely good kiter, and it's hard to get at him once he enters a bush. The role of Ezreal is to take out threats, kite the team, snipe, and do tons of damage in teamfights. A lot of Ezreal players may benefit massively from this guide. Sorry about the bad format and bad design. My main goal is to get the word across, not make everything fancy. I'll make more fancy stuff once I post it up.

Now the main goal of Ezreal is to be ahead of everyone, and to outfarm the ADC. Now, I've seen a lot of Ezreal guides and a lot of them focus too much on farming. Farming isn't about getting top farms in the game, it's about outfarming the other ADC. Either farm safely, and try to get more CS than the other ADC; or force them out of lane first and deny them farm and farm in peace. This zoning method works best with tanky supports such as Shen and Taric. This means aggresive play, but not to the point where it's stupid. Ezreal's all about kiting, so let the support tank the damage and you do the damage. When they are out of lane, switch with your support and let your support stay behind you because obviously they must be low on health. ADC isn't just about carry, you have to support the support too, it's all about the duo. While doing this, poke at them while they're under their turret low on health. It doesn't matter if you get the Q, just shoot it out in thin air just to threaten them that if they get too close, they'll die. Beware however, since your Q is down, they might lash out because your main damage skill is down.

Ezreal's juking ability is amazing, with his Arcane Shift; with the flash you can juke out before the attacker even knows you left.
Summoner Spells
Get flash and ignite always. A lot of people may argue that you don't need flash since Ezreal already has his built-in flash with him. This is not true, and may cause you a ton of lives(Also you can have fun with juking). The extra flash is always for the sticky situations. Use your Arcane Shift for a damage tool, and moreover for an escape. If your Arcane Shift is down, then you're not gonna be able to flash away from danger, or if you're chasing someone and your arcane shift is down. Flash is also a great way to turret dive(A lot of people misconceive turret diving. I see most people diving for the kill, and dying. Resulting in an equal trade). This applies to someone really low on health, not just turret diving someone on half health. Ezreal can Arcane Shift in, doing damage, maybe a q to finish, and flash out of range of the turret. With this method it's possible to tower-dive with even around 300 health. Ignite is for the finishing touch whenever you aren't able to land a few more auto attacks on the person.
Juking
Here I'm going to briefly talk about the double bush down at bottom. Earlier I mentioned zoning other carries out so they don't get farm. Make sure you're near the bushes, so you can juke if the jungler happens to come by. I won't explain exactly how to juke out, it's your own job to experiment.

A lot of Ezreals I've seen go the traditional Ezreal build and go pure damage with him. I have to argue with this because Ezreal is not a burst champion like Talon or Zed, he's an AD CARRY. A lot of his auto-attacks are supposed to be used with Ezreal in combinations with his skills. No wonder they have his passive. Fully stacked it's like another Stinger or something. Try to use his passive to the max at all times, especially in team-fights. Try timing the skills between auto-attacks to maximize your damage, and get stacks on your passive, Rising Spell-Force. Late game save your ult to initiate or snipe, since by the time you get your full build, you ult will do about the same amount as a crit.

Positioning in a team-fight has been a debate for a long time. One of us, who have common sense and keep our traps quiet instead of flying around everywhere calling everyone noobs and telling them how to live, finally is here to tell you how to position in a team-fight.
DON'T
CHARGE
IN
and also, the very best advice
STAY
BEHIND.
You're the ADC, your role is to shred their upfront defenses. Most mistake ADCs to focus other ADCs, but really as an ADC you have to attack ANYTHING THAT IS WITHIN REACH FROM A SAFE DISTANCE, BEHIND SAFETY. Make sure you're close to your team, but not too close making you vulnerable to AoE damages. Make sure you're a distance where your friendly heavy-duty CC teammates are in front of you. Don't stay too far, or you may be caught astray. Your main goal is to shred all the armor and health of the other team, reason why teams without an ADC have a hard time with bruisers. If someone is jumping at you, move into your teammates and punish that person with hard CC. When you're clear for even 5 seconds, attack some nearby minions within reach to life-steal back.

Practice. Farm. Farm. Farm. Just out-farm the other ADC by 20. 'Nuff said.