Not Updated For Current Season
Vayne is still new and I'm still experimenting a bit with her, but so far my favorite way to build her is AD. Hopefully this build will set you on the right path and spark some ideas for possible variations of the build.
I recommend watching the Spotlight video Before continuing with the build. It will help you understand how to move and play with Vayne. Don't pay so much attention to the build in the video as mine is a bit different.
Pros / Cons
Very good a chasing
Not 100% reliant on Auto-Attack
You can strategically stun enemies
Very entertaining to play
Slightly difficult to play in team fights