Yes, this is an unorthodox build for a champion usually used as an AP carry, but I have found some legitimacy in using Ahri as a AD Carry. So if anyone thinks this is stupid, it's your opinion so either hate it or love it.

Pros

Pretty fast
Decent attack range
Great crowd control spell in her E Charm
Spirit Rush allows her to get in and out of fights fast
Her Charm skill is unbelievably useful for an AD Champ
Great early damage with the combination of her Charm with auto attacking and Fox-Fire

Cons

AD does not make any of her skills stronger
Her passive also becomes almost useless
Pretty squishy (but which ranged AD carries aren't squishy?)

Runes are all negotiable, I see runes as a way to get an early step on your opponents in the early game, while runes seem to fall off from the mid to the late game. So I focused on making a rune page that would let me do the most damage in the early stages of the game.

Masteries are just purely offensive (Because you're a carry that can triple flash out of fights. If you're too close to a fight or not close enough just use your ultimate). And just some points into the Defense Tree to get some extra HP for the early game.

The items I start off with is Boots, and 3 Health Potion (sometimes 4 if I decide to wait for my 4th potion), and just farm as much as I can. If you cant farm really well, you can always Doran's Blade stack in order to get stronger and at the same time get beefier. If you can of course farm really well, you rush that Infinity Edge and try really hard to get up to that Phantom Dancer.

The items I chose are just the generic Ranged AD build I use. Of course some of the items can be changed out depending on the situation. Other great items to use include, but is not restricted to, Maw of Malmortius, Frozen Mallet, Black Cleaver, Wriggle's Lantern, Warmog's Armor, Banshee's Veil, Quicksilver Sash, Madred's Bloodrazor, etc.

Items of course should be chosen depending on how you are doing or how the opponent is doing. If the opposite team's major damage dealers are AP Casters it's smarter to get items like Banshee's Veil, Maw of Malmortius, or even Quicksilver Sash.

While on the other hand, if they start to build tons of armor, you would most likely get items like Black Cleaver or Last Whisper.

So your item sequence does not have to be the same every time you play as AD Ahri because the situations are not going to be the same every time you play Ahri.

This skill will be your best friend

The reason why you want to max out Ahri's Charm first because it gives you a crowd control spell that gets longer in duration the more you level it. You will get the most damage out of your Fox-Fire without AP to a single target (Ranged carries are supposed to attack a single target anyways) so you max that out second. You level up your ultimate Spirit Rush whenever you can so at levels 6, 11, and 16. I rarely use Orb of Deception when I play AD, except to maybe poke into bushes instead of face checking a bush. (Remember that the counter on your passive skill will go up if you hit someone with your Orb of Deception in a bush)

Your ultimate Spirit Rush is one of the best skills you have because the hardest thing for many Ranged AD Carries is that, once they get jumped on, they are pretty much dead, but the three jumps from Ahri's Spirit Rush allows you to have mini flashes that allows you to go through walls or to just create distance. Ahri's ultimate Spirit Rush also allows you to chase opponents like no other (Remember that you can auto attacking right after each jump) and if you can use your Fox-Fire and your Charm to subdue the opponent.

The summoner spells that can be used on this champ is very varied. I use Exhaust and Flash because exhaust gives you the upper hand in any type of duel situation, when you're chasing, or when you're running away. Flash, on the other hand, is not as useful because it would just be a 4th flash for you (including your ultimate) so use it if you wish. Other great summoner spells are Ignite, Ghost, and Cleanse. Teleport isn't terrible, but probably not the best idea.

You should go bot with or without a support. just focus on farming (but always attempt to hit your Charm on your opponents because if you hit that CC on them, it gives you and your laning partner a couple of potshots on one of your opponents. Try not to roam, but just focus on your lane until the team fight phase begins.

I know it's against a lot of people's rules to not be in the front as the Ranged AD Carry, but you might want to go to the front a couple times when your team and your opponent's team are having a tango in, let's say, mid lane. If you hit your Charm on one of your opponents, it drags that one champ into your team and allows your entire team to jump that one person. So if you're doing this, make sure to try and hit a carry, either an AP carry or an AD carry. (Even if you hit another type or champ on their team like a tank make sure to be very careful what you afterwards.

Yeah, so in summary, AD Ahri is very viable and I've had great success with it. You just never want to engage usually if you don't hit your Charm on the champion you want, so be very careful and cautious and be sure to only engage when you hit your Charm on a champ and make sure to deal tons of damage while you have them charmed.

Hope you liked the guide :D

*I will remember to post some of my successful games as AD Ahri as image files to this guide.