This is my build for Ashe, made to push, gank and farm.
This build is not necssesarily the best build, but it is my favorite Ashe build, and i think it makes most sense. PLZ if u find any mistakes/ have a question, feel free to make a comment. but please make it constructive, it wont help saying my build sucks without giving a reason. Vote up and subscribe if u like this build :)

Pros:
-good farmer
-hard to catch
-great pursuer
-nice pusher

Cons:
-can be ganked with stun/slow
-can have problems with high dps/tanks

Runes:
quick expanation of runes

Crit runes rule with Ashe, and cuz of the high dmg i give Ashe, it really maxes her dmg.
Dodge runes combined with evasion mastery makes Ashe able survive high physcial dmg or dps tanks.
Magic resist is good against casters, wich can be a pain normally (banshees veil is also a possibility).

GAMEPLAY

For this build, u will only need to be fairly trained at volley, and keep a lookout in the other lanes after enemys pushing/team battles to shoot in an crystal arrow. I've taken a skill in hawkshot at lvl 4 for, if i feel in threatened + any mia's, shoot out in bushes and check for enemys.
Early game:
U should try to get mid lane, wich is where I play best, but if u like teamwork with ashe, go for it :D Start with some health pots and a mana pot, wich u will problably need.
boots for some speed, wich is good against any other champ. the "Shoot runaway" technique with Ashe is preety good with high movement speed, so take advantage of that.
Mid game:
here u should have recalled (or died in worst case) at least 1 time, and u should probably have zeal. Start harrasing u'r opponent with a single shot or a vollet, and when on low hp, frost shot, crystal arrow, exhaust, volley and follow up with frost arrows + ghost if necssesary if u'r target isn't Ashed to death. I grab golem buff at late mid game, for the nice mana if possible.
Late game:
Now u can move more freely on the map, still protecting u'r lane and harrasing, but also pursuing low hp enemys in other lanes. Golem buff can probably be a must, so if golem is dead maybe go for some mana pots. With Phantom dancer and boots of swiftness u will be able to catch almost any1, and with ghost and exhaust, they shouldn't be able to get away. In team battles, u should keep u'r distance, but with slow and that awesome movement speed, u can get a few arrows on 'em even when they are in groups. Crystal arrow can really turn the tide, but should not get wasted on a group of full hp enemys (unless u'r whole team are ready to gank). I stack bloodthirster if enemys are grouping in other lanes and i cant stop 'em.

ITEM EXPLANATION

Start items:
U will start with boots for the great movement speed, wich makes u able to harras early game against any champion. Also buy a few pots, so mistakes wont cost u'r life, or to stay in lane.
All combined items:
Berserkers greaves is also a possibility, but i'll rather go with boots of swiftness cuz of the great movement speed, wich allows me to harras a bit easier. the AS on greaves is good, but if u only harras with "1 shot runaway" u wont need it that much. later in game, u COULD change boots of swift to greaves, that is u'r choice.

I buy sword of the occult for the great dmg it gives mid and late game, but dont get it at the very start, cuz the kills isn't the most important very early. Assists is also a thing Ashe is familiar with, since crystal arrow is map-wide, that gives a bit stacks too.

Infinity Edge is a very good item for Ashe cuz of her passive "Focus" ability. After recalling and pursuing a enemy, a 100% 2 1/2 dmg crit with slow can be pretty nasty. The exstra dmg and crit chance is just a super bonus.

Bloodthirster is in my opinion a nice item for Ashe, but if u really wanna change it, go put a Malady or Starks Fervor or whatever in instead. But this is my build, so im gonna go with Bloodthirster. I buy this at late game to max out my dmg, and the life steal makes it possible to take out enemy champs like Miss Fortune and other high dps types (sometimes require a exhaust too :) ). When stacked full u will own!

And at last, I made a open slot. Here, it is u'r choice. If enemy team got a tank, and i find it hard to take him down, go for Madreds Bloodrazor if HP tank or Black cleaver/ Last whisper for armor tank. If enemy team got some nasty casters, go for banshee's veil. If u go like POW out of a bush with a crit, and u shoot some volley and arrows, they either run (that means almost free kill for u) or go to attack. With that spell block at start, u can go like KAPOOW with u'r crystal arrow, and the caster should be toasted. If not, ur in trouble, and u make u'r way down to the ghost button. If the enemy team got nothing like this, u should go with Guardian angel for annoying enemys, or Yommouros (or whatever he is called) ghostblade. Many can fall for Guardian angel, and u get up and shoot their butts off. also the armor and resistance can help a bit against high dps. Ghostblade is great for some dmg, the ArP and the active. It is almost like a second ghost. u'r choice.

IF u'r new at Ashe, here's a quick skill explanation.

SKILLS

Focus

This... is... not sparta, but still, it rules. 100% crit chance after recalling, moving from 1 lane to another or even after pursuing ? Get infinity Edge with this baby, and u can harras for a couple HP :) Seriously, this is a great passive, and perfect for a champ like Ashe.

Frost Arrow

This is Ashes way to gank, capture and escape if used correctly. it applys frost to u'r basic attack, wich slows target down with 15/20/25/30/35 % in 2 seconds. When taken, it also applys frost to u'r Volley ability, wich counts for u'r basic attack.

Volley

This is Ashes main ability in my build, dmging in a cone in front of u, hitting for normal atk dmg + 30/40/50/60/70/80 exstra. It can be used at all situations. Harrasing if no minions between u and u'r target, 1v1 for the good dmg, escaping with a wide chance for slowing u'r chaser, and pursuing when enemy's around a corner or in a bush.

Hawkshot

Hawkshot bot got a passive and a active ability. The passive makes u gain 1/2/3/4/5 exstra gold for killing any unit, and the active is a "hawk" u shoot in any direction. when it hits the targeted place, it lights up a bit of the area and shows all invisible too. its cuz of the active i take it once in lvl 4. the passive is pretty good late game, but not really worth it early.[/h3]

SUMMONER SPELLS

Exhaust

Exhaust is sick for any champion (my opinion) cuz it can be used any time, any place (except when its on cooldwon xD). 1v1 u can pwn any physical dmg dealer, u can get away easily og u can capture almost any1 with this chunk of gold. It can also be used at team figts, to disable any physical dmg dealer, wich can really make a difference. all-in-all, a great summoner spell.

Ghost

Ghost is for me a very effective spell. good for getting away and make it possible to get a frost arrow on fleeing enemys. maybe not that good at a team fight, but in any other case, it rules. I find it very useful, but then again, this is MY build. if u want to change it, feel free to try Flash or whatever.

Flash

Flash is also a useful spell, both for getting away and capturing flee'ers. getting over obstacles can sometimes be a better getaway than ghost, but if it misses, u can be in serious trouble. For capturing, its good if u can predict u'r opponents move, but i like to be at their tail instead of (possibly) getting in front of 'em.

Ignite

Well, i guess Ignite can be good, if enemy's near a tower with almost no hp, so towerdiving wont be needed, but if the enemy is not near a tower, it shouldn't be necssesary. It can't really help THAT much in a teamfight, and u should be able to catch flee'ers. but if u need it, i cant stop u.

Teleport

I aint much of a recall spammer, so this spell is for me not really any help. OF course u CAN use it, maybe to get to other lanes quickly, or maybe u'r enemys are pushing u'r lane while u'r at base. But if it's really that bad, I use ghost to get there. I doesn't really feel it's a problem, but... It's not my choice.