Well hey there! Here is a guide on how to play Caitlyn, and I assure you that you will benefit from it in one way or another. Bare in mind that this is my first build guide, so I hope it isn't too bad. This guide is based upon all my experiences and learning with this champion. Here I will be giving some tips and tricks for Caitlyn, along with surviving whilst getting all the kills! If you follow this guide, you will surely be dealing way over 1000 damage for each basic attack.

For more information on the item build, skip to that section as the iconic build above isn't specific. I found it messed with the overall champion stats.

I will also update this over time with screenshots and added detail for things such as how to lane against each specific champion. When I learn how to tag stuff and add screenshots.. and also when I'm bothered to. :P

Pros:

- You can deal massive amounts of damage with just basic attacks.

- Exceptionally long range.

- You are the one who kills the enemy team in team fights while your team distracts them.

- You will always win a 1vs1. Sometimes even a 1vs3.

- Caitlyn is the ultimate carry.

Cons:

- Caitlyn is squishy and if she is focused, your team could be one step closer to losing.

- Early game ganks can set you back a lot.

- Thornmail is your biggest weakness. Do not weaken yourself unless you know it's safe to.

If you don't want to read everything in this guide, here should be a summary of most of it.

Early Game (0-15 minutes):
You want to be aggressive. Very aggressive. Only with basic attacks though. But at the same time you want to keep your distance. If you see your enemies retaliating, you may want to back off because you're too squishy. If it is a champion who has long cooldowns in their early skill levels (Vladimir's Transfusion skill is a good example), you should take the advantage to get as many shots on them before they can use their skill again. You then want to stay far back so they are forced to use that skill on minions. Once they do this, you go in to attack them again. This would surely result in first blood or a turret within the first 10 minutes.

Mid Game (15-25 minutes):
Here you should be built like a boss with an Infinity Edge and/or Phantom Dancer. Farming is a breeze, and you have total lane control. Your main weakness at this stage is ganks. Be sure to know who is mia, and ALWAYS set up traps in locations to ensure an escape route, or to spot incoming ganks. You want to make sure your lane is safe to be left alone for a few minutes while you gank another lane and push their turret. Usually when you mid, you find the team is desperate to rid of your lane by having 3 champions attempt to down your turret. In this case you should get another team mate to help and harass from the turret if they get close. If you come across a couple team fights, you should win if you keep your distance to force the enemy team to focus another person on your team. Once you see them do this, immediately try to kill the main damage dealer. You could save your poor team mate who took the focus instead of you.

Late Game (25+ minutes):
So I guess they haven't surrendered yet. Just make sure at this point you travel in a group. You will be dealing the most damage out of your team, so you NEED to be alive. Once you can achieve survivability during the early stage of the team fight you can achieve an ace quite fast. Not much else to note really. Just sit back and be safe until a team fight erupts, and go in for the ace.

Quintessences and Marks - Armour penetration is important for this champion. Mainly because this is the sort of champion that tends to rely on basic attacks to deal huge amounts of damage rather than their skills.

Glyphs - I grab cooldown reduction Glyphs because it helps with her ultimate. Also, early game CDR helps a lot because of her longer cooldowns.

Seals - Mana can be a problem with Caitlyn, which is why the mana regen/5 sec per level helps a bunch. There are times when she needs to stay on a lane for an extended period of time until she regains control. The mana regen seals work particularly mid-late game when the laning phase is over and recalling can be more than 10 minutes apart.

Some might find this to be a little odd for me to choose Sorcery masteries over Alacrity masteries. I think the cooldown helps with Caitlyn's ultimate, and the attack speed rarely makes a difference particularly in late-game when she's nicely built. The rest is pretty self-explanatory

Yes, I am greedy with Piltover Peacemaker. Because Caitlyn has exceptional range, you should be far back. So should your enemies, because of your exceptional range and aggressiveness. This is why I believe you don't need your 90 Calibre Net until level 4. Max Piltover Peacemaker first, followed by your traps, and then your net last. Obviously your ultimate whenever you can.

Clairvoyance - I chose this because I believe it helps Caitlyn more than any other spell. Firstly, if you know how to use it, you can figure out if you're about to be ganked. That is the major problem with Caitlyn. If you get ganked more than a couple times, the game is pretty much lost because you need to be alive more than the rest of the team.
The second reason why I chose this spell is because of Caitlyn's ultimate. There are too many times where I have missed out on a kill because my target disappears into the fog of war. But never again will you have this problem. Overall, the more sight you have is more of an advantage to you and your team.

Teleport - I chose this because there are times when someone may be backdooring or a lane is unattended because you carry too far as a team. It always helps.

I don't choose any other summoner spells such as Clarity, Flash, Ghost, or Exhaust for a number of reasons. Firstly, Caitlyn shouldn't rely on her skills for damage output. It should be for tactical reasons, or for the occasional cleanup of minions/last hit kill for a champion standing at their turret. If you have no mana when you can kill a champion with your ultimate, it means you're wasting your skills. Secondly, Flash or Ghost will not help Caitlyn as she is squishy enough to be killed even after she uses them (disables, etc.). Exhaust isn't necessary either because mid - late game she can clean up her enemies in a minimum of 3 shots. A game I had lasted for 1 hour and 33 minutes, I killed Annie and Nocturne in just 3 shots. Usually the battles can get so fast you may not have time to use any of these summoner spells.

Now, this is my build. This build requires a little patience at the beginning, but good things come to those who wait! I start off with Vampiric Scepter. There is nothing more important than lifesteal - especially if you're going to lane mid. Lifesteal allows Caitlyn to harass aggressively whilst still being able to lane longer and gain more gold. If you have lost health, you can safely regain it by hitting minions far back before going back in to harass more.

This brings us to our next item. Now, some of you may disagree, but I believe early game a B.F Sword is more important than Berserker's Greaves. The faster you can deal more damage - the better. You want to harass, harass, harass. At this point you want to be taking a fair chunk of their health with just one shot, which will surely scare them and make them back off (if they don't back off, you at least kill them easily). You want to deceive them and make them think you're not as squishy as you really are. But at this time, you will definitely need boots. Most occassions the enemy team will call for a gank at this point, so buy Beserker's Greaves whenever you can and place traps in the bushes.

Next, you want to finish your build towards an Infinity Edge by using the B.F Sword you already have. Again, I believe damage over attack speed is more important. That's why Phantom Dancer is next. The passive on Infinity Edge is doubly effective for Caitlyn, as it works for her Headshot passive as well as just normal critical attacks. Once you have built to an Infinity Edge, you will surely be taking a fair chunk of their health. It also makes farming a lot easier.

Once you have made it to a Phantom Dancer, the game is pretty much won if the rest of your team is doing well. The Black Cleaver is the next item to build so it makes your attacks penetrate the tanks, as well as destroying the squishy champions so much easier.

If you ever get to this point, it means that the rest of your team isn't very good, or the other team is fair game. You want more attack speed and movement speed, so get another Phantom Dancer. This helps chase down champions/run away from ganks so much easier. To finish off I wait until I can get a Bloodthirster.

If the game STILL isn't over yet, you can look into selling your Berserker's Greaves for something else like another Phantom Dancer or Bloodthirster. Whichever one you choose should be situational. I would trade boots for a Bloodthirster if they are doing a better job at pushing. Otherwise, I'd go for Phantom Dancer if it's our team doing the better pushing.

What makes Caitlyn is her team. She needs to be able to know all mias, and she needs to be with at least 2 people when going further into the enemy side of the map.

If you're playing as Caitlyn, make sure you get your team to call for mias. Always. Even if it's just for 2 seconds they are missing. Every second counts. Also, don't venture too far without being with company. If 2 people decide to gank you during this and get first strike on you, you may just end up dead.

You want to make sure you're always behind your team, and stay far back so they're forced to focus someone else. Place traps beforehand to escape, or if you're confident kill them when they are immobilised.

Farming is quite easy with Caitlyn once you have built to your Infinity Edge. You should be killing minions in 1-3 shots. Easy. You want to get as much gold as you can. But if you see a champion in range who you know you can sneak a few shots on, then by all means do it. ;)

Farming only gets easier and easier the later the game lasts. Near the end of your build, you should be killing minions in just 1 shot. If it gets to the point where one of your inhibitors has been destroyed, you can deal with the waves of super minions by yourself in no time and let the rest of the team do something else more productive.

If you go to an unattended lane with a build-up of minions coming towards your turret and another team mate follows, tell them to go away (politely). You can handle the whole wave by yourself, even if they're all attacking you (lifesteal). Plus, the more gold you earn the better the outcome of the game.

So that's it! Caitlyn is a beast of a champion who can deal a load of damage throughout the whole game. Be sure to play safe, and be aggressive when you can. Build her right, be patient, and devastate your enemies!. Think strategically by planning your escape before a fight, and be wary of your approach. With a good team on your side, you will always win!