Vayne Guide

Tips for Playing Against Vayne

-A good Vayne is theoretically nearly impossible to deal with I think, but I think all the Vayne's I've played against have only picked her to counter me, and weren't Vayne mains. This makes the matchup way more playable.
-The idea is to play REALLY safe early. Max range Q minions (this is easier to do if you take Doran's Ring, as it gives extra mana).
-Never use W on her unless you 100% hit it and won't get kited to death. This likely means she has to not only have just used Q and then got slowed by you, but is also flashless.
-A bit sneaky, but sometimes you can laugh emote to bait her into trying to roll away from your Q. After she rolls, you can land a Q a little easier.
-This matchup gets a little easier later, but you always have to be careful, especially whens he uses ult. You can W away to avoid her when she ults, but make sure you won't get condemned into a wall.

Heartsteel

Heartsteel is perfectly fine I think. The extra range on Q is nice, and the flat damage from TK's passive and Heartsteel's passive will chunk her since she's so squishy. I've never had a Vayne prove to me that this is a bad choice.
Doran's Ring

D-Ring is a bit counter-intuitive, I know. The idea is that you get extra mana to max range Q minions (or her if she comes up to attack you, in which you'd also get healing from that), and you'll never run out of mana. I think it's actually super necessary in this matchup.
Swiftness Boots

I think Swifties is the only boots answer here. It's great in general, but against Vayne it is super necessary for escaping, chasing, and repositioning to not get condemned into wall. I believe Tabis is a complete bait here, especially given her W does %HP true damage.