Try to combine a tempest of steel, with a blade in the wind, you will farm better.
With the short waiting time of his "Steel Tempest" Yasuo can harass his enemy too much. He tries to charge your tornado and then you put a wall of wind, you rush against the subjects until you reach your rival and make your tornado hit.
If you want to be aggressive use windblade on minions to reach your opponent and use Tempest of Steel directly on him and then use windblade to exit (to ensure this, start your "combo when the next wave of subject)
You can also use Blade in the Wind against a champion or minion followed by the third charge of Tempest of Steel, this gives you a pretty good cc, in exchange for (if you have used it against the champion) spending your blade in the wind on it. This combo is pretty good at securing kills on low health enemies. You can also finish the combo with your ultimate and followed by another tempest of steel. Use this combo only on certain occasions.
You can use Geometry to launch a wall of wind behind your opponent's back (assuming you are facing melee with him) followed by a blade in the wind for a safe and instant shield.
Using blade in the wind with subjects in a chase is a good way to catch up with your opponent.
You can use the combo of blade to the wind and the third charge of steel tempest to use that cc that it gives you while your jungle ganks your line, casts a cc ability or others, you can also use only the third charge of steel tempest, but with the aforementioned combo you assure melee rank with your enemy. You can also do combos with the flash, like when an enemy is at low health and is very far away. Throw blade to the wind on a minion and at the same time Steel Tempest to do it in a circular way, and just before the Steel Tempest flashes on the enemy and you will do the damage to him.