I understand that alot of people believe that akali is hybrid, but it really depends on the way you want to play her but in my case i like her ap for the max skill damage. Since the item changes and buffs and debuffs. i had to update my build but there are multiple ways to build her and her item build can be changed dependin on who your opponents are playing and how well you are doing.

Pros:
-Awesome Chaser
-Heaps of outburst
-Very good at running away
-Fun to play
-Good at keeping stacks
-okay at 1v2
-fed akali = GG as most ppl say

Cons:
-squishy early game
-targeted if you have alot of stacks
-expensive items

Summoner Spells:
Ignite: good for all sorts of things like finishin someone off that you dont want to chase stopping some annoying character from lifestealing/ healing.
Flash: this skill combined with twilight shroud can get you out of almost any dangerous situation as long as you use it wisely.

Core items: Hextech Gunblade - it is something that i would always but nv for 1st item, this item gives spell vamp which is a bonus to her passive. because of akali's low cooldowns you can almost spam her spell which makes it very effective along with the lifesteal of this item.Socerers Shoes- i believe that this item a more suitable boot for akali rather than the mercury threads. it isn't exactly necessary for the cc reduction because if your tank can tank properly they will be taking most of it in, also the twilight shroud will protect u from most cc's because of the stealth.Rylai's Crystal Scepter- this can be said as my favourite item for akali. not only does it give an additional slow, but loads of ap and hp. there are some people who complain about the squishiness of akali but with the help of giant belt (recipe item for rylais) she is almost unstoppable.

Other items:Mejai's Soulstealer - the main reason why this isn't a core item is really because if you arn't doin well at the beginnin and early mid of the game there really isn't much point of this. Mejais and Ocult are items which you get near the beginning of the game for the benifit of the end game. if you get this later in the game it really goes to waste.

Luxury Items:Rabadon's Deathcap- the reason why this is in luxury is because it really is expensive. i hated the removal of zhonya's ring, but this will have to do. despite the price it is worth how much it is. this one item can increase your ap from 300 to 500. Don't leave it to last item, because your last item depends on what situation is goin on with ur game.Lich Bane- The mp part of this item goes to watse with akali which is really a shame, but the passive is excellent. you can use the passive at all sorts of items includin killin towers. If you have alot of ap (say 500 for instance), the hp of the tower just drops instantly. It also give an 7extra movement speed, not really needed but it comes in handy at times.

Optional Last items:
Lich Bane, Void Staff, Zhonya's Hourglass
This last item is really your choice. i would normally get lich bane because it helps me kill towers so much faster, but at times i would switch to void staff if the enemy team is buildin alot of magic res. i have only ever get zhonya's hourglass if they have an oracle and are focusin on me, that rarely happens since not many people are bothered to waste 400 gold on that.

Laning Parners:
i love lanin with tanks, they would normally take in the damage and makin it completely safe for akali to kill.
It is best for akali to lane with someone who has a stun. Snears and airborn are also good, but stuns are always the best.
When there is a jungler i would always take the solo lane as long as there is no eve, gp, tryn, or blitz on the other team. These are people who will be givin you a hard time and tower dive you often. Apart from blitz but his pull pretty much causes as much problems.
There are times that akali would take mid but that is only if there is no mage on your team (soraka doesnt count).

Beginning Game:
Start off with a Amphying tome and a health pot, now if your lucky you would have at least 1 kill when you go back which brings you to around 1500gold at or at least 1000gold for me it is a habit to get giant belt first because i love to towerdive. From what i see other akali would normally get hextechs revolver. Also don't forget to buy your boots, at times i would forget about this item but it really is needed.

Early Mid Game:
This is normally the time that i get Mejais dependin on my k/o rate. if i m not doing too well and can't keep myself alive i would skip this and just build my rylais. At the time you get mejais, don't do stupid stuff. it doesn't matter if you are akali or not your not invincible. Towerdiving for one kill isn't worth losin 1/3 of your stacks (unless they are worth 1k gold)

Mid Game:
Your mejais should have around 10 stacks right now, even 7stacks is fine. Don't go around ksing like crazy tryin to get max stacks you are not a carry. 10 stacks would be enough to make your enemies hate you for your outburst. Your carry will need the kills to have a successful end game. I would either choice to finish my hextech gunrevolver or put a start to my rabadon's but that depends on how much money you are able to get.

End game:
If you still have 10 stacks it is fine dont think you are failing coz it is hard to keep stacks as most people will focus you. If your carry is successful you would be at least at the end towers. This is akali's time to shine. Your carry won't be needin any of the kills anymore since they would already have enough damage. If your team is losing, as long as your team and you play smart you can make an epik comeback. Pick wisely for what last item you would get.

Extended Game 1hr+:
There are times that games go on for longer than an hr, at that time most people would be fed up with it, as for me i won't mind if we lose as long as my k/o are positive :P. But at time when i m desperate to win the game i would sell my boot and buy one of the other optional last items, it makes me a little slower but with lich bane i m still able to keep up. It is really unlikely that games would go on for this long so it isn't something most people would worry about.

Attack Combo:
I have 3 attack combos one of them my friend recommended and the other 2 are just one that i used and became a habit.

Friend Combo-
Q>R>W>E>Q>Exhaust if the run>R and they should be dead

My Combo (sneak)-
R>W>Q>Exhaust if they run>E>Q>R and they should die

My Combo (normal)
W>R>Q>E>Exhaust if they run>Q>R and they die :D
*put w directly on them or behind them


Things that Akali players should take note:
I know that everyone is different and play her differently, but there really is something akali should be doin.
Dont aim the tanks, its not akali's job what she does is pick on the squishies and than kill the tank. At times i see random akali's takin on a rammus, it isn't impossible but why would you do that when u can be killin some little tiny teemo its not worth the time.
Also something to think about, dont tower dive for unneccessary reason. Know your enemies skills and think before you towerdive. everyone makes mistakes and miss calculate their moves but at times it is better to not have a kill than to be greedy.
Something that everyone should know, a carry does not mean the most kills and Akali is not a carry. she starts off great at the beginning and is great throughout the whole game.

Ranked Games:
when you reach ranked games it would be a lot harder then you expect and you would often have a jungler
if thats the case i suggest you tank solo lane, don't afraid to tower hug people who are over confident would tower dive and underestimate your outburst and... they would die which lets you have a free kill :D
for ranked games it is best if you do not chase enemy champs too far unless you are sure that no other enemys would be around
sometimes you would need a bit more survivability so getting an armor isn't a bad choice i would recommened Banshee's Veil, or Guardian Angel
Banshee's blocks a spell which is very useful at times it also provides a pretty good amount of hp but the mp part would go to waste
Guardian Angel it gives you an extra half a life :3 also adds armor and magic res

Akali is a great character to play, but as most poeple say she is op...
i really don't have anything to argue against that because simply one rylai can make her tough to deal with. She isn't a hard character to play but to play her skillfully it takes time, to learn the many tricks she can play with her shroud (:

Technically my name isn't odelle but my friend just calls me that coz i look the same as this yr 8 guy (im a girl btw). and sorry about the language we use :P its just our way of saying Hi to eachother

sorry about the quality of this one i had to take it with my ipod because i was at a net cafe. anyways this is the photo of the ap from the picture above with the 18/2/13 score (:

This game really pissed me off coz it took so long n it went over my bed time :/ but i was really satisfied with the amount of ap, 2hits and one turret is dead :D
If someday i have time i would record some videos for this guide :D