He is probably THE BEST laner against Yasuo. I play 10 champions on a regular rotation and Vladimir is my counterpick against Yasuo.
You want to rush to 40% CDR through runes and itemisation (build components as necessary... ex Codex and then Lucidity Boots and then Kindlegem). You should not need to build Seekers but if you are uncomfortable with the match and/or he gets ahead... built it. It doesn't matter what you build so long as you rush to 40% CDR ASAP.
Once you get comfortable with the match-up, you can dominate Yasuo for days.
Your first priority is to NOT DIE. If Yasuo so much as gets 1 kill, the lane is over. That's the kind of BS champ you're playing against. Luckily though, Vladimir is a good champ for the matchup.
First stand back and auto farm. Early levels you want to keep your distance, use your autos to proc his shield. If his shield is down, poke with Q. YOUR Q GOES THROUGH HIS WINDWALL.
DON'T USE E IN THE LANE AT EARLY LEVELS. Its not worth it. Just auto and Q. ALWAYS keep your distance from him. Side step the tornadoes, you don't have to dodge everything but you need to dodge enough damage so that on average you are sustaining back what he does manage to hit. You have no mana costs so you can do this ALL DAY.
Don't worry about killing him, the longer it goes, the more it favours you because few champions can match Vladimir's overpowered late game.
As you are poking him, watch his heath, if he gets to 33% (he really shouldn't get there but some Yasuos will fall that low)... If he gets that low.
- Auto him to make sure his passive shield is gone
- Watch the Crimson bar, just before you get the empowered Q charge your E.
- Flash into him and pop the E on him.
- Hit him with Hemoplague (it can't be blocked by Windwall)
- Hit him with Empowered Q
- Follow up with autos
- Pool if you have to to dodge his attacks
- Ult will Pop on him.
Dead Yasuo.
Repeat.
If you get 2 kills on him you can kill him over and over again with ease. Just be careful about minions and his windwall blocking Tides of Blood though.
Anytime it looks like has has an advantage, step back and sustain, auto and Q at him. Always keep your distance. If you have a good enough lead, start dancing around and hitting a few Es at him.
Late game and in team fights, don't Ghost into the fight until you know where Yasuo is. If he gets caught by your allies, go in and nuke him to death. If Yasuo starts a fight and tornados... wait for him to go in on your allies then you launch your counter attack against him as he's Ulting your team. (Ghost + Hemoplague + Qs and Tides of Blood)... your team will probably come out on top due to the counter initiation.
Once Vladimir gets to 4 to 5 points on Tides of Blood and has the build to support it, he can 1 vs 2/1 vs 3 with ease.