Akali is a very versatile champion. She can chose a path of AD/AP/Hybrid and especially tank.
As season 6 comes, koreans made akali a top destroyer for any opponent, which is the tank path. The tank type is a very simple way of playing akali because you just have to stand beside your opponents and just spamming E. Akali's E has a very low cooldown ( 1 sec. ) when maxed making her a very scary opponent especially with the new mastery called Grasp of the Undying.

In early game you should just focus on cs. When your enemy is also killing the minions, use your E on minions when the champion is in your E's range. When your opponent is a range champion, stack your Grasp of the Undying while killing minions and go straight to the enemy champion then hit them and use E.

Meelee:
Zoning-
Minions+Champ = use E
Minions = Normal Hit then E when they go near you

Range:
Minions = Use E
Minions>Grasp of the Undying > go to enemy champ > hit + E go back to your minion wave.


Have Bami's Cinder/Sunfire:

Use W on enemy minion wave> Go inside and wait for Grasp of the Undying > Hit + E the champ > go back to minion wave or inside W range. Repeat.


Clash:

Wait for Hard CC of your team or the other team to be used > R on ADR/AP/Squishies> E > Q > Hit > E > E > E > Use R to clean up tanks and supports and spam Q + E

Note : Prioritize squishy targets and no escape targets before the tanky champs.
Don't commit to 1 v 3-5 when you know they have many hard CCs and when you dont have bami's cinder, Iceborn gauntlet, Tiamat.


When 1 vs 2: ( Winning chance 75% )
When 1 vs 3: ( Winning chance 45% )
When 1 vs 4: ( Winning chance 15% ) up to 1-2 kills
When 1 vs 5: ( Winning chance 10% ) up to 1-3 kills. 5 kills when fed.


Use R on the most squishy champ/No escape champ > Q > Hit > E > hit > W > Hit > E > Hit > E till he/she dies then quickly change target to the other one > Q > E > hit > E > hit > E > Hit repeat