Hey, Xin is an amazing champ, and I will do my best to show you how to play him as i play him. I on average 7 games with him for everyone one loss. I would like to thank you before hand for reading this guide and would love for any feedback and suggestions to improve it. How i play my game style is at the very bottom, so please read all the way through or this guide will be useless.

Pros
-Massive damage
-Easy kills from ganks
-Massive lifesteal and attack speed late game
-When ganking and your not focused in fights, triples and quads regularly occure
-

Cons
-Very Susceptible to ranged Dps champs (Vayne, twitch, etc)
-Low health with my build
-Easy target early game for tanks and ranged dps
-When focused by more than 2 champs can go down easily

I use these runes because they help a ton, they aren't your average run of the mill runes for a fighting dps champ. I choose the mark of desolation simply because of the amazing early and mid game damage boost it gives me, as well as the quintessences. Now the Alacrity rune i use because in early and mid game your attack speed isn't what it needs to be and this helps solve that problem, those stacked with the phantom will give your 2.5 or just under. Now as for the glyphs, many people think i am stupid for choosing the CDR, but numerous times i have had to wait for cool downs when i could have gotten several more kills in a team fight, or assisted my team with them, this simply solves that problem greatly.

I take a full 30 in offense because in mid and late game you should have your bloodthirster with your cleaver and will be getting massive Regen from it all. So there is no need for the other masteries to be put in place.

My item choice is chosen for maximum effectiveness in mid and late game. This means you NEED TO BE CAREFUL EARLY GAME. Unless you have been fed with the help of your laning partner you must be careful as you have very little life steal and health as it is.
-I choose the boots for escaping dangerous situations in early game and the potions to help keep lane dominance, you can switch one HP pot for a mana pot if you feel its necessary, now the boots will also help with attack speed later on. I don't see any alternative for this build, the boots I keep all game.
-The cleaver in ways is the core item of your build, without it you will be ripped to shreds against any tank and thornmail user. This item also helps your with attack speed later on and is an essential.
-This item is also a MUST without this you will be toast in any fights, remember to FARM the jungle or minions!!!! if you don't the life steal will never reach its full potential. This is 3rd because this should come into plat late-early game or early-mid game and is crucial to survival of team fights.
-The phantom is the bread and butter in this build, it gives you massive DPS help and critical strikes are amazing late game. Without this you will get no where as you will never have enough Attack speed to do anything real serious to their team
-Infinity is the final item, and most of the times if you play this build right you wont even get to it :( But when you do need it, its extra critical strike chance as well as the 250% passive with its damage, will make you a deadly opponent and virtually unstoppable.
-This second infinity is simply there for the extra damage it gives, if needed you can switch it with a warmogs for more health or atamas impaler, but normally i got with a tiamont to make sure to get some damage on their entire time during big team fights.


EDIT: If you want to be more Tanky Buy a warmogs in place of the infinity blade. You can then either continue and buy an infinity or buy an Atamas Impaler

I use this sequence for max damage, i delay the battle cry because of the runes and my early game set up, but it can help late game at times. I try to switch between Audacious Charge and Three Talon Strike in my build as they are the most damage effective, and of course my ult whenever possible. Ill explain how I use the skills later on.

I choose Teleport and Ignite, Ignite will get you plenty of early kills and help late game to reduces some health from champs. I choose tele mainly because of its mid and late game potential, tele allows me to get to the team fights fast if i am not near them or push a lane faster with a group of friends.

I play xin and a Bottom Lane Dps fighter carry. Remember: BOTTOM LANE
The early Game:
Xin early game is honestly pathetic and without a cooperative laning parter you will not do well!Xin does his damage from ganks and help from the turret at this stage, that being said TURRET HUG! people may call you a ***** and noob, but this will WIN THE GAME later on. DO NO, i repeat DO NOT push unless a jungler is ganking or you are AT LEAST level 7 and have basic items. ALWAYS lead with Audacious Charge and IMMEDIATELY activate Three talon strike for extra damage, this is where those CDRs help a TON!!! they will allow you to Audacious charge again for another slowing effect for easy kills. That is how you play early game, play smart, dont push to aggressively and WAIT for them to dive you or a gank. If no ganks or dives are happening wait for early items and level 7 AT LEAST and push them.
Mid Game:
By this time you should have at least Berserkers Greaves, a Black Cleaver and a Vampiric scepter, at the minimum. With this build you will be able to sustain in a team fight and do some nice damage. Now in mid game you need to push your lane and start ganking mid and top lanes for extra kills or assists, that will help get your build faster, if things are going bad across the map turret hug, kill then buy items and coordinate ganks with your team to take out their carries. ALWAYS FOCUS THEIR CARRIES, if you do not they will destroy you. Now if things are going good, ALWAYS gank at least mid and push your lane. Just farm minions and some jungle and get your build at this point at the game, and help your team as much as possible.
Late Game:
Late game is where the killing happens. By now you should have all but your infinity, unless you've done really well in farming and getting kills. This is when you need to gank in a team fight, have your tank lead and the rest of your team follow in, then you come from the side or cut the off from behind and use Audacious Charge, then three talon with battle cry all in sequence, if you are about to die waste your ult, its got a short cool down, if they are running repeat above process and when they are at the edge of your ult hit them with it for kills. By doing this you will be doing massive damage and they will all start to focus you eventually, but because of lifesteal you will be able to either sustain, or sustain long enough and do enough damage while taking at least one or two out before dieing and your team cleans up and pushes, but most of the time you should be able to live through a fight if your bloodthirtet is maxed out and your cleaver will tear apart heir amour, including that dammed thornmail!
The mid-late game is where you get fed and carry the team the most, as long as you follow the build and play style, and your team cooperate then you have got a game under raps as a carry.

Once again thank you for taking the time to read this and any feedback or advice would be greatly appreciated. This is my first guide so tell me if you like it. Have fun all and may the fields of justice serve you fairly!