Why jungle xin, U gank so hard,and (early game) if ur target is at 600 or under they are almost definitely dead, if no routes are gankable just get a minion or 2 from the closest lane, recall and buy a madreds
http://www.youtube.com/watch?v=Lgvebcglr3E

USE THE Tanky ROUTE its somewat slower but u have enought hp for a gank
Use the MASTERIES IN THE VIDEO, MY RUNES WORK :P or u could use stonewall's , watevs

Pros
Great farmer
Great Pusher
GREAT GANKER
Great early game
and late game
Crazy damage output and sustain
tanky, high damage, you eat the squishies

Cons
-Somewhat dependent on Blue buff for decent jungle speed early game
-If u dont do much dmaage until u buy BF sword (u are more of a support in a fight knock up precent damage with ult)
-If they get a frozen heart u must trust ur team mates to take out hte person with the frozen heart or u wont being doing as much damage
- malphite screws u

You're a jungler => marderds and boots
then --> HoG
it gives u hp for safer jungling, ganking, money for wards and the rest of ur items
(will pay for itself and then some)
then -->avarice
Ur building a yoomus, mite as well get this guy early for the gold (will likely pay for itself and some extra gold -enought for a ward? maybe 2)

U can build Mercs or SotD in any order (i like to build a 1st bow if i can)

So yeah, u wanna get ur knock up to work fast, by maxing battle cry, SotD and Black Cleaver u will have max attack speed when active.
Attack speed on xin synergies with everything about him:
-your cdrs(battle cry)
-heal (passive:tireless warrior),
-damage (knock up and auto attacks)
SO get SoTD

After ==> BF sword or Brutilzer
U have most of ur attack speed now u need damage!!

Then==> yoomus (if ur struggling to stay competitive) or Black Cleaver (i prefer this first as it raises ur attack speed to that 2.4 cap when used with battle cry and SoTD active, plus ur avarice will be making u more gold =D )

Once u've build ur yoomus or black cleaver u can
-build the other one
-get some tankyness

If u are doing fine build the other and have 90 armour pen with yoomus active and Black Cleaver stacks (no problem with u insane attack speed)


Your Last Items/Tanky Items (hog and madreds aren't final items)

Your melee so dont be so squishy, other builds that neglect survivability means ur relying on ur team to support and perserve u
"yo check me out i do 500 a hit then i die cause im so squishy"(well with max attack speed u do 500 a sec with like 90 armour pen (from autoattack only) but watevs)

YOU can build a ur madreds into wriggles any time, a bloodrazor only if they are just stacking hp with lil' MR<== i usually sell it to help build my bf sword sooner, if not i sell it for mr, but if ur owning really bad or they haev no magic damage, then idc if u wanna keep a wriggles or build a blood razor

mr, for mr go for a banshees or QQ sash(i like qqs over banshees just cause u decide when to ignore the ccs coming at u, but banshees gives u some hp but thats pretty negligible if ur stuned or silenced and ur taking more hits cause of that,

Your HoG
Its made back to total gold it costs to make and more, u got a good 2 1/2 ish wards from it at elast (depends when u build it though it should be built rite after ur madreds and boots)

for armour u can finish it and get a randuims and a sunfire (or thornmail, idc i'd get sunfire for some hp if randuims isnt really relevant (like ur enemies haev no attack speed)

After u are done ur build (this happens in most games over 40 minutes in length)==> get shiny
Buy the elixirs and oracles and u are now shiny xin, dont run in first in the team fight so u can pick off the squishys once they appear, u can 1 v1 anyone (cept tryn, well maybe depends how much damage he does cause ull make him endless rage in like 3 secs), and turrets fall fast

Cresent sweep > Battle cry> 3 Talon > Audacious

3 Talon
-AWESOME knock up and damage, guides that tell u to max this first for the damage assume that u will be able to land the 3 hits somehow and make the knock up (when xin has no cc), i build attack speed so I can land them all on the same target if i wanted to, and to knock up without any help(cc) from allies
- if u do have cc from allies consider using battle cry after the knock up cause the cd timer of this skill starts after the knock up

Battle Cry
- This is ur bread and butter --> cdr for other skills and attack speed
the cdr for this skill is the true cdr time of ur other skills (cept ult),since once this is up ur other skills will also be up real shortly if not already up

Audacious charge
-If u want damage early game this is it, as once u use it ur attack timer is reset and an auto attack is quickly made rite after the use of this skill
-its closes the gap between u and ur target (u can easily focus the guy u want to ina team fight)
-last hits :P noe u when the turret is about to hit it ;D

Crescent Sweep
This is a great ult, percent damage plus insta-tank and can be used in practically all the fights as cdrs aren't relevant because of battle cry

Early game & mid game- use it at the start of a fight only if u can hit several targets or if a cc has kjsut been applied
-use it to land the kill(it does a base damaage too) when ur target is nearly dead and is fleeing or watnot

LATE GAME- U can use it to clear minion waves only if u are confident taht u can get the cooldown over in time for the nxt fight
In a team fight use it rite away making sure u land at least 3 ppl in it

U will finish ur build in most games sooner than ur team mates and do this:
knock up once every 5 secs, do 500 damage a sec with 90 armour pen (just autoattack), crazy ult that takes away like 8 % of ur enemies health and turns u into a tank
Just Own them