Hello,this is the first guide i have ever done so please comment so i can then make it better.

This guide if you have not seen above covers three champions: Ashe, Master Yi, and Nasus.

The Champions I play best as are Master Yi and Ashe. I first Mastered Ashe by accident and kept trying different builds on nocturne, found one i liked and killed everyone thereafter.
I Mastered Master Yi second and almost never die.

If you looked at both of the rune pages you can see that they both use the exact same runes. I use the same runes because with the armor pen it will make it easier to kill other champions (mainly squishies) in beginning game. The armor for a little extra survivability. the health for well health and survivability. And the attack speed for easier kills.
If you didn't notice i have damage dealing runes for a tank. I will explain that. With nasus as a tank you need kills every here and there. the easiest way to do that is with the runes.

I use 21/4/3 for Master Yi.
Use the offense for faster kills.
Use the defense for survivability.
Use the utility for the mana regen and only the mana regen.
I use 21/0/8 for Ashe.
Use the offense for faster kills.
Use the Utility for faster leveling and mana regen seeing as how much mana her spells cost.
I use 3/22/5 for Nasus.
Using the ability power in offense to deal more damage.
using the defense to take a hit and live.
and using the utility for mana regen, mana, and when you die rezzing faster.

Master Yi: Start out with the boots of speed and three health pots. soon you should have eough gold for the Berserkers greaves(early game attack speed), next an eblem of valor and a recurve bow(early life steal), and a zeal.
Around the time you get your zeal it will be pretty close to mid game.
at mid game quickly get your phantom dancer. start building your cutlass or revolver(i dont care witch one first) and get your gunblade. Use either the gunblade or Infinity Edge. Purchase two B.F Swords then turn them into Bloodthirsters. Its easier to buy the two B.F swords than it is to buy the B.F sword and a vampiric Scepter.

Ashe: Start out with a Doran's Blade. next buy a dagger and boots of speed. Quickly buy the berserkers greaves to get an early advantage against your enemy. Buying a phantom dancer really early is probably the hardest thing to do if you use this build. Buy an infinity edge and another phantom dancer and another... then sell your doran's blade and buy a black cleaver. Whe nyour finished you shoukd have a 2.5 attack speed and a 100% crit chance making your passive obsolete.

Nasus: First purchase a Doran's shield to start you off. using the shield for armor and health regen. next buy a boots of speed and either buy a ninja tabi for armor and dodge or buy a mercury's treads for magic resist depending on what kind of team your facing. buy a chalice of harmony because at the beginning your going to have mana troubles seeing as how your going to kills minions with siphoning strike. buy a warmogs for extra health. Buy a rabbadon's deathcap for extra damage with ultimate. buy a moonfire spellblade for extra magic resist or a thornmail for extra armor. buy a gaurdian angel last for armor magic resist and a rez every no and then if you die.

Master Yi: Many of you would and probably think why in the right mind would you use Wuju Style first. Well, combined with exhaust and ignite it turns out to give you first blood almost every time. The skill order is Highlander > Wuju Style > Alpha Strike > Meditate.

Ashe: Ashes skill order is Enchanted Crystal Arrow > Volley > Frost Shot > Hawk Shot.
For my build you'll need hawk shot at level three to get more gold to buy the build a lot faster.

Nasus: Max out siphoning stike first and use it to kill every minion you can. max Fury of the Sands next. maxing out Spirit fire will help. max wither last.

For master Yi using exhaust and ignite give you many kills early game setting you up for mid and late game.

For Ashe using ghost can get you out of sticky situations and using ignite to get the kill if they run away.

For Nasus use Fortify and Teleport. Using Fortify will save a turret and might give you a kill. Use teleport to try and save a turret or allied Champion.

So over all. Master yi: ignite and exhaust. R>E>Q>W. Two B.F swords before your two Bloodthirsters. Extra mana regen. And more damage

Ashe: Ghost and Ignite. R>E>Q>W. 2.5 attack speed and 100% crit chance. Extra mana regen and survivability.

Nasus: Teleport and Fortify. Q>R>E>W. Choose either armor or Magic resist. Extra mana and mana regen. dps runes.

Master Yi Pros

First Blood every time.
Easy kills
Harder to kill

Master Yi cons

Still squishy

Ashe Pros

Only a little harder to kill
Fastest kills ever
Easy kills ever

Ashe Cons

Still easy to kill
cool downs still long

Nasus Pros

Harder to kill.
Can still deal out tons of damage.
Can save turrets and champions.

Nasus Cons

Can still be killed if ganked.

In order for you to get the builds for both Ashe an Master Yi you'll need to jungle every now and then. For Master Yi whenever you can get the lizard elder buff and dragon buff(three v.s. three). As Ashe get the ancient Golem Buff and the dragon buff(again three v.s. three).
Get as many minion kills as possible and kill as many champions as you can WITHOUT dieing.
If you die it will be much harder to kill enemy creeps and champions.

For Nasus killl the ancient golem when you can. and kill ALL creeps with your siphoning strike to increase its damage.

As Master Yi in a team fight aim for the squishiest champion first so you can get Highlander and Wuju Style again.
As Ashe in a team fight aim for there strongest player to use your crystal arrow on to stun and give your team a small advantage for the three or so seconds it stuns for.
As Nasus use Spirit Fire to reduce their armor, use fury of the sands to damage them a little more. if you die guardian angel will save you and you'll have to save everyone else again...

I have never done a ranked game yet, so when i hit summoner level 30 ill try these builds and tell you how well they work.

One of master Yi's unique skills is that when he kills a champion all his cooldowns are refreshed.

One of Ashe's unique skills is that she naturally has a high attack damage and attack speed. Even at level 1.

One of Nasus' Unique skills is that he has an ability that increases it's damage when a creep is killed the damage will increase.