Not Updated For Current Season
Summoner spells are the key to winning games and the summoner spells you use are crucial to your gameplay, it is important you use the summoner spells that are most beneficial to you and help you out in the most ways.
Optimal Summoner Spells
First like to I take exhaust because it's amazing for early game killing which Vayne excels at and securing kills, it can also be used to shutdown carries, casters, and keep someone from tower diving you. It is in my opinion one of the most versatile summoner spells in the game. I take this with most of the DPS champions I play.
Second I like to take flash because it's just amazing and can be used in many ways just like exhaust. You can escape, get into position, chase, and get away from towers after getting that first blood. It can also be used in combination with tumble for some awesome results.
Possible Summoner Spells
Ghost- If you feel the need for ghost then take it in the place of exhaust if you want extra escape abilities. Flash and ghost together can be a good combo on ranged carries however I prefer having one offensive spell and one defensive, especially because Vayne already has 2 escape spells, Condemn, and tumble. Let me also explain the reason I take flash/exhaust instead of ghost/exhaust like some people would. First off, chasing opponents will not be hard at all because if you forgot, you have your lovely passive that gives you a huge chunk of bonus movement speed when chasing enemies. Having ghost and this would just be overkill, your much better getting a more versatile reliable chasing/escaping summoner spell.
Clairvoyance- Now before you say "'w-w-w-aaaaaaaaaaaaa?!?!?!? she's not a support champ u don't need dis noob gtfo with ur noob spells" think about Vayne's passive, it gives bonus movespeed while moving towards enemies, only applied when you have vision of them. Say you chasing someone down the river and they flash over a wall, you pop clairvoyance and you now have sight so that little bit of movespeed can sometimes help you catch up. Again I wouldn't totally recommend this it's just a thought.
Ignite- This is the last spell I might consider, the extra damage from this is great for getting early game kills and countering Dr.Mundo/Vladimir. If you get this you can role with exhaust ignite for an amazing early game, or flash ignite for a safer high damage play style.
Night Hunter- (Innate): Vayne ruthlessly hunts evil-doers. She gains 40 Movement Speed when moving towards an enemy champion.
This passive is pretty sweet for chasing down enemies and REALLY helps you harass in early game. If you have movespeed quints you should have total control.
Tumble- (Active): Vayne tumbles, maneuvering to carefully place her next shot. She rolls toward the cursor and her next attack deals bonus damage.
This ability is straight up beast with only around a 1.5 second cooldown once you get some items. It makes your attacks deadly strong and it's amazing for harassing.
Silver Bolts- Vayne tips her bolts with a rare metal, toxic to evil things. The third consecutive attack or ability against the same target deals a percentage of the target's maximum Health as bonus true damage. (Max damage vs. Monsters is capped at 200)
This is a pretty nice ability and it's great against tanks, it makes killing jungle creeps pretty easy, however you must remember the debuff only stays if you stay on the same target.
Condemn- (Active): Vayne draws a heavy crossbow from her back, and fires a huge bolt at her target, dealing damage and knocking them back. If they collide with terrain, they are impaled, dealing bonus damage and stunning them.
This is basically like a long range version of Poppy and it works wonders, it's great for interrupting all kinds of ultimate's and pulling off other cool stuff.
Final Hour- Readying herself for an epic confrontation, Vayne gains increased Attack Damage, stealth during Tumble, and quadruple the bonus Movement Speed from Night Hunter.
Final hour is pretty much your attack steroid and you can use it for chasing, escaping, 1v1, and much more things. Always use this when entering a fight and killing towers because its cooldown is short too.
Team fights can sometimes be hard with Vayne, do your best to stay in the back and snipe people using tumble, make sure not to tumble into the enemies by accident because you will most likely die, try to tumble backwards and move back up to take the shot. Use condemn whenever possible but try to hit enemies into walls DO NOT EVER HIT AN ENEMY AWAY FROM THE FIGHT WHILE THEY ARE GETTING ATTACKED UNLESS THEY ARE VERY LOW ON HP, YOUR TEAM WILL GET MAD what you should do though is use this to knock out the tanks and supports while your team brings down the squishies, you can also use this to save allies. If you have very good tanks you can probably stay in battle constantly and attack, when your not focused your DPS can be pretty insane and it's easy to get triples and quads. Remember to use your ult in the beginning of every fight, it will help...A LOT.