I am gonna tell you how to make vayne the bursty yet sustained true damage carry!

Extra note: For support go someone like Thresh, Leona, Taric, or Soraka.
Supports that either have hard cc and engage that let's you catch up or someone with sustain to help the early game

In the laning face your weak.
You will be behind your minions, just last hitting with the help of your q, so you don't miss any.
Make your support ward brushes so you won't be caught by any CC.

After you get Blade of the ruined king, you can begin the pressure your enemies.

In late game fights don't use tumble towards enemies, use it sideways or backwards to still be away from enemies.
Use your ult at the end of the teamfights or if you get focused. It will make you able to switch targets easier.
Remember to use tumble to position yourelf so you can condem people into walls, that extra stun and damage can lock down and kill a champ.

if you find yourself in a 1v2 versus adc and support. If they have low CC you can pop ult and tumble towards them for a free condem on the adc into a wall. This can make your 1v2 succed. Remember to keep kiting from side to side.
Your statikk shiv will become ready faster this way and you might just evade som skillshots.

Vayne could easily go as the strongest champ in all of league, but her complex mechanics make her a hard choice. She has few counter and her counters aren't that strong. She has the perfect fit of utility, damage and crowd control to make her the most important thing in your game.