The type of champion Akali is, is a little bit unique, she is an assassin (that she jumps in trying to finish off the enemy ADC), but her damage isn't instant. She has combos and in 90% of the times, she needs to play around her shroud (W).

Passive (Assassin's mark): Using an ability on an enemy champion creates a large ring around them. If Akali leaves the ring, her next auto attack is enhanced with bonus range and damage. She also gains a short burst of movement speed.

Q spell (Five Point Strike): Akali throws knives in a direction. They deal magic damage. Enemies hit at max range are slowed.

A tip for using Akali Q: Is to make sure you always keep a track on her energy, it's easy to get caught up in using her Q as the CD is so low.

W Spell (Twilight Shroud): Akali drops a smoke bomb and restores some energy. While inside the smoke Akali is invisible and untargetable.

Attack and abilities briefly reveal her.

E Spell (Shuriken Flip): Akali Throw a Shuriken and flips backwards. The first enemy hit is marked. Akali can dash to the marked target.

Akali's shroud (W) can also be marked and dashed to.

R Spell (Perfect Execution): Akali Dashes to a location, stunning enemies in her patch.

After a delay, she can dash again. The second dash deals execution damage to enemies in it's path.

You can also extend the range of both R casts with flash!

In the lane, you always want to hit enemies with the tip of your Q to proc passive aa instantly.

So it will be like this Q > P aa > Q

Skirmish combo:

E > P aa > Q > W > P aa

Most basic assassination combo:

R > E > P aa > Q ( > W > R)

Melee matchups are easy in comparison to a mage with long range.

Your best bet in the laning phase is to farm up with Q and shroud. Your goal is to survive mage poke.

When you hit level 6 you will most likely have the opportunity to go for a kill against mages.

Akali loses to a lot of tanky/bruisers matchups like Renekton and Kled.

How to win hard matchups is to freeze as close to the turret range as possible.

Look to abuse Akali's level 6 and Hextech Gunblade powerspikes.

Akali can almost take every single roam route from mid lane, by using her E to jump over walls.

Typical roam pathing: Go to enemy raptor entrance E or plant over Krug wall and come from behind.