Alright this is just the way I prefer to play Xin, this is also my first build that I have put on this site. So critisize all you want. I play Xin kinda selectivly depending who the other team has.

The runes I like to use are Armor Pen Marks and Quints, Attack speed Glyphs, Seals I just use Armor/lvl since it helps throughout the game.

I go with 21/0/9 but you can change the 9 to be in either defense or utility.

For the items I like to start with Doran's Blade since it gives him everything he needs to start. After I go back the first time I like to try and have enough for boots and a B.F. Sword but if I don't I just grab boots. Around mid game I usually have The Blackcleaver and upgraded boots which makes it very easy to get kills and farm off minions. What I usually lhttp://www.mobafire.com/league-of-legends/edit-build?edit=61959#ike to try and do is wait until I have enough to buy entire items like The Bloodthirster, or Frozen Mallet but if not just go ahead and buy the parts needed to make it. I only put in 5 items for end game since the last item can be interchangeable depending who your are going against or the amount of damage you are taking or something like that but most of the time I usually would buy a Banshee;s Veil.

My skills I like to max out Audacious charge first, followed by Battle Cry, With at least one or two points in Three Talon Stike for the damage.

Preferable spells for Xin
Exhaust- Very helpful for Xin to make sure he gets those early kills or easy ganks, I recommend this skill.
Ignite- Helpful for gettin those easy kills when the other guys are at low health or just getting the kill on Tryndamere after his ult wears off.
Flash- Good for getting away from the tough spots or setting yourself up for easy ganks.
Ghost- Good for getting to those teammates that need help or chasing someone down.
Teleport- Well teleport honestly isn't a spell that most people use on Xin but it could very well be used for staying in lane longer for more experience or jumping to another lane real quick for a gank.

Not as important spells for Xin
Clairvoyence- Well this spell helps to reaveal the map, but its unimportant for Xin.
Clarity- He does need mana, but this spell wont help him very much when hes in fights, save this for those casters that constantly use mana.
Cleanse- Could help him get away from CC effects but honestly they shouldnt be happening to Xin.
Fortify- Sure it helps the team but Xin doesnt need this spell at all.
Heal- This spell helps but its not the best for Xin.
Revive- Well, you shouldnt be dieing so dont need this spell.
Smite- Mainly used for jungling which my build is not for but hey take it if you wanna kill Tibbers.
Rally- More damage but not exactly suited for Xin.

So yeah, this is how I like to play my Xin, I do pretty well with him most games, but we all know that we have the one or two bad games so take this build for a spin, and tell me what you guys think! :D