Easy, because he dominates the lane, with continuous q pokes & whirlwinds, dashes for extra damage/reach and a w that can block there attacks a good yas can zone any ranged carry.

Pros:
High Damage
High utility
Can block range carries attacks
Only Need Randuins to survive in team fights with most comps
Free shield if you constantly move and dash
Great pushing power

Cons:
Squishy
Always on the move
if your not careful you can get yourself zoned

First things first, avoid being hit, continuous running for your sheild and poking with ur q then e dashing into the bush will stop the majority of damage enemies try to dish out.

Offensive behavior: Yas is pretty bursty usually you want to start out by dashing from a bush onto a minion using q to poke then dash to another minion back into a bush. When you build up to ur tornado strike place yourself in a position to farm and hit the enemy carry.

once the carry or the support are low enough dash to a minion close to them if u can tornado q if not q em Ult them and aa until u can e dash to them and ignite them to kill them. It is important to note they will probably be running so e dashing to minions along the way will not only increase your e dash but help you stick to them

Denying Farm: One Great thing yas's w can do is safely deny the enemy farm or making them risk close range damage. Timing your w so you block all you minions will allow turrets/other minions to kill yours instead of the enemy carry, sure they can run in or to the side to snag some but that will allow you to e dash to them and q them before they will get near it. If you have your shield charged you will take little to no damage

Setting up your ult: (Usually I have a support with knock-up just in case)When the enemy carry & support is around 3/4 health each my support and I try to knock em up, Usually with my q. Once then I ult then go for the kill dashing to minions near the target to build up the damage on E dash (It is important to save the E dash on the target itself for max damage and to make sure you can stick to them)

Starting Items:

A pot and a Dorans will be enough to sustain you against most bot lanes, just keep aaing and qing for health and last hits

For trinkets I usually use Sweeping lense to prevent auto attacks in bushes, if they are not warding then switch to the ward and ward ether there bush or yours.(remember to buy wards for river/tri bush b/c the stealth wards last longer then your free ward)

First Back:

I usually pick Vamp Sceptre Wards and potions but depending on how I do and on different team comps I tend to mix it up a bit.

Health potions, I get at least 2 but usually more depending on what I have left after my other Items

Wards, Usually one or 2 but as Health pots I buy more depending on my extra gold aafter items

Vampric sceptre is a fav choice of mine, with the added damage and life steal you will stay in lane all game

Boots a must not only will it help your engages but it will build your shield up faster

Avarice blade great for earning money fast, with your fast clear times you will be swimming in cash in no time

Zeals Crits, Want quick ms and crit? well there you go

Second Back:

These are really situational, if you are doing well build towards an Infinity Edge if you need defense build towards Randuin's, Sustain I usually Get after the other to because it is so dependent on the enemies build. As for boots I usually build Boots of swiftness and usually on the second or third back

Boots of swiftness: Need more speed? Ashe arrows got you down? Want to gank more? This is your answer!

Cloak of Agility: want 30% more crit? by this time you should have avarice or Zeals so that should give you a comfy 50% crit chance

Warden's Mail: Just shy of getting the kill? Dying to much from champs with fast autos? Well slow them down a bit with wardens.

Giants belt: Extra health never hurt anyone, I usually get this after warden's mail since warden's has both offensive and defensive capabilities

Big ****ing Sword: Destroying lane? Want to farm the enemy champs faster? This is your item!

Quints: 2 movement speed and 1 crit damage
The movement speed help you engage/disengage and allows you to build your shield faster While the crit damage will help counter your 10% crit dmge reduction

Marks: Crit Damage to help with double crit chance

Seals: #FLat armor to help you deal with those adcs

Marks: Great for Late Game magic resist

Offensive:
4/4 Fury. Can always have attack speed, not only does it work well for autos but lowers the cool down on your q.

1/1 Butcher: helps with last hitting

1/1 Feast: Helps with Lane sustain

3/3 Brute Force: Helps with last hitting, Harrass and generally everything damage

1/1 Martial Mastery: Same as brute force but instant instead of over time

3/3 Executioner: I take this over Spell/Blade Weaving b/c It helps me kill low health opponents which could be hard when dealing with certain carry / support combos

3/3 WarLord: Because 5% more damage is awesome

1/1 Frenzy: With double any other champs crit Chance this little beauty will stack really fast

Defensive Masteries:

2/2 Recovery: Helps you stay in lane

2/2 Block:Helps you take less damage during your pokes and Helps you stay in lane longer

1/1 Unyeilding: Same as block

3/3 Veteran's Scars: More health means more survivability

1/1 Juggernaut: more late game health

3/3 Hardness: Makes dealing with those adcs a bit more easy

1/1 Reinforced Armor: Reduces damage from crits

So you have killed both bot lanes or have at least crippled them, What not? Well thanks to his Speed there are a few things you can do

Gank is your mid a first time fizz having trouble getting his kills? Is your top still learning how to counter a rival he hasn't encountered b4? Well gank for them! and make sure you don't go taking all the kills. It is important to improve all your teammates so they will have to rely less and less on you throughout the game. Remeber a team that shares kills shares a win.

Invade "oh pretty buffs, mind if I take em?" If your other teammates are doing well why not invade the enemies jungle? Take red or give blue to someone who will need it more then you (because lets face it your cool downs are low enough and you don't need mana). This will not only give your team a friendly boost but weaken the enemy junglers which means he will have a harder time picking off you or your teamates.

PUSH!!! The reason I put this last is because it is the most obvious and easy thing to do, Just remember to ward so you wont get ganked.

Like the Guide? Have a question? Have something you want to discuss? Drop it in the comment section and I will be happy to discuss it with you.

as the title says, I will be working on this constatntly updating if you have any questions or want some advice just leave a comment