I'm not a very good ranked player, just because I only do well when I have one of my friends as support playing Thresh or Rakan. Both of us are Mastery Level 7 with the lovers, and play them remarkably. I have mained Xayah ever since her release, I was fascinated by the feather concept. I had a little help starting, and soon enough I was getting S+'s left and right with my friends, and I shot her up to Mastery level 6. With a good support and good adc skills, Xayah is an extremely good champ.

Xayah does a TON of damage, her abilities are so fun, everything you do makes you look good, her skin is hot, and do you need more?

Pros and Cons to playing Xayah
Pros
+She has a lot of damage potential
+Her abilities are simple and there's not many secrets to learn.
+She deals damage faster than she can die.
+Escaping is easy with her.
+She does ALOT of damage late game and is really useful in team fights.
+Her Q and E don't increase in mana cost when they're upgraded.
Cons
- She has low mobility.
- She doesn't have a lot of health, and doesn't last long in the center of a team fight.
-She can be hard to control at times, and needs a lot of farm and a perfect support to get a good game.

Essence Reaver: Requirement. Get. It. First. This keeps you from running out of mana. Until you get this, don't spend time poking and damaging your enemy. Spend it farming - once you get this, then start poking, and make sure to get minions while you do.

Berserker's Greaves: Always get boots second. This is for more attack speed, if you're enemy laners aren't good at farming and aren't good bot laners.

Phantom Dancer: Keeps you from getting minions blocked early game. You can damage the enemy but if someone else comes, makes it a lot easier to run like a coward. (Which is very useful with Xayah)

Infinity Edge: A must have. Gives you a lot of damage on crits, and you will have a lot of crits with this build. Almost every auto attack will get you mana back, giving you a lot more opportunities to root in team fights.

Bloodthirster: If you're facing hardcore tanks, getting this and Mortal Reminder will help. This gives you more damage when you don't crit, but gets you ALOT of health back when you attack minions. Best paired with Statikk Shiv because when you build up your lightning, attacking one minions will get you half your health back.

Mortal Reminder: If someone has a lot of health regen, this is great. It stops that regen so you can take them down fast in team fights, then killing the squishies in the back.

Statikk Shiv: For farm. Good with life steal, as stated on The Bloodthister.

Frozen Mallet: Pure tankiness. Gives a lot more intimidation and potential in team fights, also slowing the enemy with every auto attack, also good in team fights, and good for Xayah because instead of wasting time on getting movement spend on yourself, you can just cancel theirs.

Mercurial Scimitar: For life steal and magic resist, if you're facing hardcore AP champs.

Thornmail: Use if someone builds a lot of life steal and AD late game. This counters their life steal by causing damage as fast as they steal life from you, so they don't get much health back. Any damage you do, you should be able to steal right back, if you use life steal. Also good against AD tanks with lots of regen because the Grievous Wounds counters it.

Rapid Firecannon: Helps with life steal. Increases critical strike chance by ALOT, so you'll get a good amount of life steal out of a single auto attack. Also increases attack speed, dealing ALOT of crits.

Ninja Tabi: Get if you're having trouble against an ADC on their team. Only if they are a HUGE problem.

Guardian Angel: For some armor and some more damage. If you get this, save it for last, cause it's not that important. Will give you more usefulness in a team fights, cause if you are targeted, which you should be behind tanks, whoever targeted you will die quickly. And even if they kill you, you'll come back, making them waste a life.

Runaan's Hurricane: Only if you're going all out attack speed and crit. This is a good move, especially against tanks. You'll be able to attack fast, dealing crits on almost every auto. Also helps with farm.

Ionian Boots of Lucidity: I'm pretty sure Xayah is from Ionia, so maybe her Mom made these for her or something like that. Anyways, gives more CDR for faster and more often roots in team fights, and increases movement speed for easier escapes.

Mercury's Treads: For magic resist. Pure. Magic Resist. And I guess it helps with being stunned... Also they look pretty cool.

Heal: For intimidation early game. If you're at half health, bait your enemy laner. When they go in, you go in, and heal. You'll move faster, and all of sudden, not be that worth going in for.. and dying for.

Flash: For escapes purely. If you don't know what flash is for... you're not ready for Xayah.

Ignite: Can be used instead of heal if you have a support with heals. This is for guaranteeing kills early game so they don't run off with ONE FJKSFLNHSF HITPOINT!!!!

Smite: PLEASE DON'T TELL ME YOU'RE ABOUT TO JUNGLE WITH XAYAH!

Barrier: Not very useful unless you're mid with Xayah, which is hard to do. You face too many counters, but if you can face them, use this against ults or potential mass damage.

Exhaust: Kind of like what I said for Frozen Mallet. Instead of them being faster than you, you just make them go slower, and you kill them faster. Not very useful due to cooldown, and doesn't have a purpose if you use frozen mallet.

Ghost: Not useful. Takes too long to start up, and doesn't even increase by that much.

Press the Attack: Hitting an enemy champion with 3 consecutive basic attacks makes them vulnerable, dealing bonus damage and causing them to take more damage from all sources for 6s. She's an Attack Speed champ, and this makes her attack speed more useful with increased damage after three hits.

Triumph: Takedowns restore 15% missing health and 25 bonus gold. Gets you some health back and some bonus gold. Useful, very useful when compared to other rune choices.

Legend: Bloodline: Takedowns grant permanent life steal. Life Steal, as I have covered, is VERY useful with Xayah. This gives her increasing life steal making it REALLY hard to kill her late game.

Cut Down: Do more damage against enemies with a higher max health than you. This is useful If someone has less health than you, they're dead. Everyone has more health than you; you're an adc. Takedown tanks faster, and take down pretty much everyone down faster.

DOMINATION +18% Attack Speed

Taste of Blood: Heal when you damage an enemy champion.
AHHHHHH MORE LIFE STEAL MWAHAHAHAHA!!!

Ghost Poro: When you enter brush, a poro appears. It will stay behind to give you vision. Helpful when you don't have a ward. You can put this in one of the bushes, and then you no longer have to ward that bush until the poro moves.

PASSIVE - Clean Cuts Description: After Casting an ability, Xayah's next three basic attacks strike all enemies along their path, dealing 100% damage to her main target and 50% pass-through damage to all other enemies. At her maximum range, a Feather will be left in the ground for 6 seconds. Xayah can store up to 5 empowered attacks.

PASSIVE - Lover's Leap Description: Xayah and Rakan can recall together.

PASSIVE - Clean Cuts Explanation: Take advantage of this. With Xayah's E, if three of those feathers left in the ground hit an enemy all at once, the enemy is rooted. When you use Xayah's Q, you only have 3 feathers for this passive stored due to the Q counting as the first two. A good combo with this would be Q when the enemy is very close, then auto attack them once as fast as possible, then E for an insta-snare. An even better way to do this is to Q, and then W during the Q animation. This cause the Q animation to go by faster, and then you will be able to auto attack almost immediately after using Q. Now, use E, and this snare comes even faster and gives the enemy a lot less time to react.

PASSIVE - Lover's Leap Explanation: This is very useful when with a Rakan support. If he sits in a bush an recalls, use this time to get farm, and when his recall is about half way done, walk to it, and you will recall with him in a bout 2 seconds if timed right.

Q ABLILTY - Double Daggers Description: After a brief wind-up, Xayah hurls two feather-blades in quick succession in the target direction and leaving two Feather on the ground at maximum range.

Q ABILITY - Double Daggers Explanation: This is only good early game. You get this first, but max it last. The reason you get this first is because you don't use much mana with the pokes, and it doesn't have as long a cooldown as your W. When you get E (which you should get 2nd), you use Q when they're are within at least half you maximum range (halfway between you and your max range) and auto attack once as fast as you can, then E, for a quick root if you did the combo right and fast enough.

W ABLILTY - Deadly Plumage Description: Xayah surrounds herself with a storm of feather-blades for 4 seconds, granting her 30 / 35 / 40 / 45 / 50% bonus attack speed, 20% increased damage on her attacks, and 30% bonus movement speed for 1.5 seconds when she attacks an enemy champion.
If Rakan is nearby, he will also gain Deadly Plumage.

W ABILITY - Deadly Plumage Explanation: Get third, max first. You need to get E second for snares, but once you hit level 3, snares will be MUCH faster. Maxing this first will give you that attack speed fast, and the extra damage. The combos with this is Q, W during Q animation, aa the target, and then E for an almost insta-root. Also, when you have feathers left over from this, try to hit minions in the line of an enemy champions, getting a bit of damage on them while farming. Also use this ability while attacking turrets.

E ABILITY - Bladecaller Description: Xayah calls all Feathers back to her, dealing physical damage to enemies they pass through (Increased by Critical Strike Chance). Hitting an enemy with 3 Feathers roots them for 1 second. Minions take 50% damage from Bladecaller.

E ABLILTY - Bladecaller Explanation: This is my favorite ablilty. Your roots come from this, and a TON of damage coms from this. A good time to use this is when you have three or more feathers down and at least three will hit a single champ, rooting them for 1 second. Like ive covered, the early game Q, W, AA, E combos is really good and gets you bonus damage early game. Another combos with this is to R, then E. If you used R on a champ that is right next to you, when you E, all five of feathers are likely to hit them, rooting them and dealing a lot of damage. After using E, your passive still applies, giving you five more feathers to stick in the ground. When attacking Epic Monsters (drakes, Rift Herald, Baron Nashor, Vilemaw, etc.) Use Q, lay those three passives, use W, lay those three passives, and then E, dealing the damage of ALL 10 feathers laying in the ground (if you have enough attack speed so the feathers stay in the ground long enough).

R ABLILTY - Featherstorm Description: Xayah leaps into the air becoming Playful untargetable. She then rains down daggers which deal physical damage and leave behind a line of 5 Feathers. Xayah can move while in the air.

R ABILITY - Featherstorm Explanation: As I have covered before, use this with E if a champ is lined up for it. Another combo with this ult is if the enemy champ is near the edge of its range, Ult, but as soon as Xayah ducks to throw out the blades, flash in that direction and then E for a surprise root. Then, W and auto attack until they DIE.
Another way to use this is if you are about to die, ult and flash away, or ult over to a tower, since you are untargetable. You cannot be killed in this unless you have a sever poison or bleed. This makes as a threat to make people run, and makes you invincible pretty much for a couple of seconds.