I want to say thank you for taking the time to read my build. I only ask you try it out before you say anything about, good or bad. This is not just a build but it's a guide to help all you Caitlyn players out there. I will explain all of my choices but, since I'm a short and sweet kinda person, not all of my explanations will be extremely long. well hope you enjoy!

This is for those people who are too lazy to read. Caitlyn is squishy meaning she is very weak defensively but is legendary when it comes to offense. Building up her piiltover peacemaker early game will help you harass your enemies early game or when a stalemate occurs late game.
Never try a 1v2,1v3,1v4 or 1v5. Always try to stick with a tank or support champion after mid game. try to stick to item build and skill sequence. Whenever your laning partner/s goes for last hits or gets distracted harass them until they go hug the turret. Only go for last hits minions early and mid game try not to auto hit them till late game. Use your passive to deal a good amount of damage to your laning partner/s as much as possible. Whenever you get a champ weak and they start to run away use your ulti to crush their hopes of escape. Never use your ulti to start a fight and that's about it. hope you actually take the time to read my guide.

I mostly have attack speed runes on because Caitlyn's attack speed is god awful until late game. Putting on runes that help early game give you an advantage in mid lane. But if you're amazing at last hitting minions then i suggest instead of as runes use armor pent. runes instead. i also suggest that you have mana regen runes as well, this is because you want to be able to spam cait's abilities and since her mana pool and regen are terrible it helps to have all mana regen seals and glyphs, then put marks and quints as armor pent.

The masteries I use are just used to my personal play style. My personal opinion though is that any carry should have 21 points in attack and 9 in utility. Possible changes that could be made is you can take 3 points off from archmages savy and offensive mastery and put them towards sorcery. But like I said that's my personal mastery setup, it just fits my playing style. the second caitlyn tree is the one i use currently but the first was also good too.

I personally suggest you stick to the item order only cause I believe it'll benefit you while laning

The reason i start of with a doran's blade is because its just an amazing early game item. the lifesteal can actually be the deciding factor in a fight. and the bonus health it give is really helpful. I chose berserkers greaves because it helps cait's attack speed early game and help you with last hitting creeps. As for the vampiric scepter, it helps you stay in your lane longer then you think. That's why i suggest getting it early. The Black cleaver is extremely useful item and i recommended you get it as quickly as possible because it gives you a lot of ad and gives you a good amount of armor piercing. Since caitlyn is a squish getting the bloodthirster is very helpful late game when team fights start up. Next i suggest that you get Stark's Fevor because it will increase your lifesteal and a better chance to stay in the fight longer. Now this is the part where you can play around with the item order. i suggest you get phage before you get phatom dance but if you feel you need the attack speed asap get phantom dancer first. It all depends on what you are up agianst.

Also depending on what your up agianst and you playing style you can swap out frozen mallet for Infinity edge or stark's fevor for another bloodthirster

The skill sequence is pretty basic. Getting your peacemaker up early will help you harass you lane partner/s and leveling up your net can help you get away from a gank and it can help you get away if your having trouble staying in your lane early game. Many people use the Cait's trap but personally i only usually use it when I'm on the run. i place it right in front of me so when I walk over it'll be harder for them to dodge

The summoner spells I choose are merely to help you escape whenever you get into trouble. Try not to use them unless you have to.