Hi! Im _Dev_ManGoNicK from Garena SG/MY server. Although i have low ELO but sometimes a noob maybe good at something. Like im good at Yasuo. I have ranked-phobia as there is alot of trolls and afks. Yasuo is a hyper carry if you played it properly. Some comment for my guide please :)
P/S: You may use it at bot lane too!

Im still trying to figure out S4 Masteries. But this mastery i found it the best.

Doran Blade lets you harass well in lanes, as early game they are squishy.
You may starting to play aggressive once you got Statikk Shiv
Also, use your item active only when you met someone you barely able to fight with.
With this build you can burst ADC less than 3 seconds and a tanker less than 8 seconds.

Q is your main damage source, max it first. While E you can juke people like hell, by dashing around with minions and combo it with your Q. Use your E to positioning to place your tornado. With minions Yasuo is OP. Also, ignore the critical chance at the top, its 80%!

Use your E Often, it works to dodge enemy skill shots and you can combine it with your Q to attack in a circle. Keep use it and use E & Q to harass when enemy is trying to farm. Also, a ward is essential to dodge jungle ganks.

Ask your jungle to take someone with knock up (Xinzhao, Wukong, Leesin etc.). It can increase your chance to land your ult when jungler is trying to gank. Stay behind tank in teamfights, communicate with your teammate to get some of the minion waves if you are teamfighting in lanes or get some neutral monster in jungle in order to get your tornado. Always remember, NEVER LAND ULTI ON TANKERS(unless you face to face a tanker and you have confidence to fight with)

Well, I think these is enough. This is my first guide ever created and thanks for reading. Kindly leave comments on what to improve.