Things to take into consideration:
It does not really matter when you first take your Windwall, change when you take it depending on the enemy jungler and laners, but I would definitely take it before hitting level six.
Jungle Path: Red Buff -> Krugs
Yasuo has a really strong early game compared to some other junglers, by going Red to Krugs you are instantly level 3 and you have the possibility of ganking top (still level 1) or mid (level 2) or going for an invade.
Yasuo has some really easy jungle wave clear, so don't feel scared picking this
You will sometimes meet the enemy jungler at Scuttler after your Red to Krugs, don't be afraid to fight him.
You are strong all game, however, I would say that the strongest point is when you get your late game rageblade. This will double the on-hit effects of Wit's End, Hydra, Bloodrazor, The Fervor of Battle, and Bork... and your Q ability also procs all these.