Tips on beating yasuo?

The closer your champion can handle the fight being, the better off you are. Yasuo's high-impact patterns are almost exclusively closing distance and dropping burst. Someone who can mitigate that, or turn a melee brawl against him easily, without being a victim of his wind wall would be great picks.

I've heard that Nasus is a strong counter, as is Darius. Nasus gets the elements of poke and a nasty slow, and can bring down the hurt if Yasuo gets close, after some Q stacks. When he hits 6, Nasus can probably safely walk all over Yasuo, barring him getting a significant lead. He has nothing that Yasuo can Wind Wall, and Wither will take a lot of the wind out of Yasuo's sails (ha, ha). Xin Zhao, Jax, maybe Garen and maybe Warwick and almost definitely Fiora would all be fair picks. Picks like Gangplank, Quinn, or other ranged-intensive champions will probably flounder against a Yasuo skilled with Wind Wall.

Yasuo doesn't have a lot of flex room for builds, as his crit bonus limits him in a few ways. Champions who can respond to his build without breaking their own (IE bruisers) will have a far easier time. Point-and-click CC like Vi or Malphite ults will do some damage.

Naturally, armor is a good build. Yasuo's penetration from his ult is now only applied to crits, so it narrows in on the ways he can respond to armor builds. Randuin's hits all of Yasuo's buttons, from health and armor, down the slow passive and active. For more offensive inclinations, Dead Man's Plate will be readily used and he has poor resources to keep its stacks down. The extra movespeed can provide an edge for slow contenders like Darius, who may need the nudge to keep up to Yasuo's dashy retreats and engages.

You may not want to take AP-centric champions as Yasuo can max crit and obtain MR/dmg builds with relative ease-- after which, between his shield and Edge of Night or Banshee's Veil, he'll dole out a lot of punishment and take little in return, while still possessing his rushdown patterns.

Yasuo's ult is a pretty predictable pattern. Get in the habit early of avoiding the Q-nados, and you should experience better results through the game. The path is thin, the travel time is fairly quick but it has a modest hitbox and range in a straight line. Hard mobility like Riven jumps will avoid it easily-- leaving him to charge up two more hits. If he clears his area, then the only stacks he can get are in melee range with you.

Lastly, you probably don't wanna ask boards.

Just pick Darius and make the Yasuo rage quit lol

Pretend to lose lane and let him push you under tower and poke you with q's till you get a gank