Ashe is one of the strongest AD carry champions in the game. With a devastating ultimate and amazing damage output, Ashe is a champion to be reckoned with. In this guide, I dive into two possible ways to play Ashe, each one completely viable in today's metagame in my opinion. Check out both pages for variations on masteries and runes. The items and the item build are consistent.

Pros:
-Great damage
-Poking ability with volley
-Game changing ult
-Can slow enemy champions
Cons:
-Very squishy
-No abilities to help get away such as Corki's Valkyrie; summoner spell reliant somewhat
-Weak early game until you get your items

9x armor pen marks are the best in slot; Ashe needs this to put out damage
9x mana regen/lvl seals are the best in slot; needed for Ashe to use her abilities on a consistent basis
9x AS glyphs or 9x MR/lvl glyphs; either works; depends on your style of play as well as the other team's composition.
3x armor pen Quints or 3x AD Quints; both help Ashe in the damage department. AD Quints feel better early game while the armor pen Quints help out late game. Adding a flat HP Quint or 2 is not completely out of the question in this slot either.

Ashe can go two ways in Masteries.
A 15/0/15 build gives you sufficient damage power in the Offensive while giving you extra Mana regeneration, movement speed, and lower cooldown on Flash.
A 21/0/9 build gives you the most damage output, while giving up the attributes previously stated with the 6 extra points put into Utility.
Use the build that you are comfortable with. There is not only 1 way to play Ashe well.

For summoner spells, I take Flash and Ghost. I feel the Ashe, unlike other AD Champions such as Corki and Ashe, does not have the abilities that help him when caught out of position. Therefore I feel both Flash and Ghost are essential. Ignite is possible if you are in a solo lane and use it to land early kills. Exhaust is also often an option on AD carries.

Ashe can be played either in a solo lane or in a dual lane with a support. Should you lane in a solo lane, start off with boots and 3x health potions for mobility to dodge enemy abilities as well as to position yourself for last hitting creeps. The health potions are to help for a successful laning phase that allows you to farm for a longer period of time. If you are in a dual lane, I suggest starting off with a Doran's blade. It gives you more damage to last hit creeps efficiently and to harass the enemies in lane. The support player should help you with healing and such. On your first trip back to base, pick up another doran's blade or two if you are struggling with your farm, or a BF sword. Picking up a few potions and a ward are not discouraged either. Get your berseker greaves for extra attack speed or mercury treads should the opposing team be stacked with effect abilities. Pick up your Infinity Edge as soon as possible as it gives you the best damage output as your first main item. Get a zeal next, turning it into a Phantom Dancer for attack speed, crit strike, and movement speed which is essential on carries. At this point in the game, I feel that Ashe can go a variety of ways. ALWAYS LOOK AT THE ITEMS YOUR OPPONENTS ARE GETTING AND BUILD ACCORDINGLY. You can go with a Banshee's Veil should you feel the need for the item in the current situation of the game. You can pick up a Bloodthirster for the life steal and sustainability in team fights. An extra Phantom Dancer isn't out of the question either. Get Stark's fervor if they are just stacked with tanks. Black Cleaver is an option ONLY if you are way ahead in the game. People may ask why is Last Whisper chosen over Black Cleaver? Black Cleaver gives you better damage early-mid game; however, there are better items that give Ashe damage in those phases of the game, such as Infinity Edge and Phantom Dancer. Late game, the 40% armor penetration you get from Last Whisper outweighs the extra AD from Black Cleaver. Also, most teams don't stack up heavy on armor until the match reaches late game, it it does last that long. Don't forget elixirs when you're ready for important team fights and pushes.

Max out Volley first, since it's your main source of damage and farming ability until you get farmed. Put a point into Hawkshot for scouting purposes and then max out Frost Shot. Take Enchanted Crystal Arrow whenever possible since it is so powerful and one of the best ults in the game.

Initiate team fights with Enchanted Crystal Arrow, but only when it wise to do so. If you initiate with your ult while your team is not in good position, then your team is at risk of getting wiped out if you team decides to follow up. When team fights begin, stay back of your team. Always attack the enemy champion(s) who are safe to target. Never put yourself at risk by chasing down targets; let your teammates who are in better position and have champions that are better suited to finish off enemy champions to do so. Use Flash and Ghost when necessary.

1. Abuse Volley.
One of the reasons why Ashe is so strong is his ability to poke with this skill. Use it to farm, to harass, to slow, and to poke to get extra damage on the opposing team before the team fights actually initiate. Using it behind walls, cliffs, and towers is often a good idea.
2. Hawkshot is underrated.
Use this skill on a consistent basis to check for ganks and on important parts of the map such as lizard/golem buffs, dragon, and Baron. It is basically a free moving ward. The extra gold from the passive is nice too!
3. Positioning is key.
As an AD Carry, you have a responsibility to your team to position yourself wisely and die as least as possible. I prefer playing Ashe with Berserker Greaves and damage items instead of getting Mercury Treads/Boots of Swiftness or getting an early Banshee's Veil. Why? Because I know how to position myself and I feel that getting items that benefit my damage are better than getting items for survivability. Position yourself wisely!
4. Farming is important.
I often find myself in games where a player on my team chooses to be the AD carry and chooses to harass heavily or to gank as opposed to focusing on farming. Harassing is good, but not at the expense of your farm. This is even more important for Ashe, who is heavily item dependant to put out damage. A good barometer I use is 100CK by 15-20 minutes. If you reach this, you are doing relatively well; even better if you get to that point earlier. If you're not good at last hitting/farming, maybe AD carries is not the right role for you!
5. Learn when to use/not use your skills.
An example of this would be Volley. Volley is your main source of damage early game. However, by mid game you should have items that give your auto attack more damage than spamming Volley. At this point, stop using Volley and use it only when it is absolutely necessary to do so (to slow multiple champions for your team). Watch your mana cost when using Frost Shot and only toggle it on when you feel that you can help land a kill for your team. Leave it off otherwise. And finally, Enchanted Crystal Arrow is arguable the most important skill in the game. Should your team be based around your ability to properly initiate with this skill, practice landing it and learning when it is wise to activate it.