Yasuo vs Garen

Hit twice with Steel Tempest (Q), on minions if needed, to charge the whirlwind. Cast it during Sweeping Blade (E): the strike becomes a circle.

Keep moving before taking a trade: Way of the Wanderer (passive) builds your shield while you move, and it triggers on the first hit you take.

Chain Sweeping Blade (E) on different targets to reposition or dodge: each target has its own cooldown, so the spell comes back almost instantly.

Save Wind Wall (W) for a projectile that decides the teamfight, like Jinx's ult, rather than for poke: it blocks for 4 seconds, on a 25 to 17 second cooldown.

Watch for your allies' knock-ups: Last Breath (R) can be cast on any airborne champion, whether the knock-up comes from your whirlwind or Malphite's ult.

Hit him regularly, even with a small poke: Perseverance (passive) only regenerates him if he hasn't taken damage recently.

If you're ranged, kite him: his kit has no dash, and only Decisive Strike (Q) speeds him up and removes his slows.

Wait for the Courage (W) shield to end before your burst: the spell starts with a shield and tenacity, then keeps only a damage reduction.

Once he hits level 6, back instead of staying in lane at low health against him: Demacian Justice (R) deals true damage that grows with your missing health.