Akali vs Yasuo

After each spell that hits, step out of the Assassin's Mark (passive) ring: your next auto gains range and damage.

Mark your target with Shuriken Flip (E) before leaping with Perfect Execution (R): recasting Shuriken Flip takes you back to them, even after your leap.

Cast Twilight Shroud (W) to dive under the enemy tower: inside the smoke you are invisible and untargetable, but an auto or a spell reveals you briefly.

Save the second dash of Perfect Execution (R) to finish: its damage grows with the target's missing health.

Hit him with a cheap attack to trigger the Way of the Wanderer (passive) shield, then start the real trade: otherwise, it absorbs your best damage.

If you have projectiles, save them for after Wind Wall (W): it blocks them all for 4 seconds, on a 25 to 17 second cooldown. Other spells go through it.

Don't stand right behind your minions: each one gives him a target for Sweeping Blade (E), and he gets closer to you with every dash.

Get out of the line of his whirlwind, the third Steel Tempest (Q): without a knock-up, he can't cast Last Breath (R).

Judge his threat by his crit items more than his level: Way of the Wanderer (passive) raises his critical strike chance, so each crit item does more for him.