Vayne is a very high damaging, mobile, ADC. She, in my opinion, is one of the strongest ADC's, due to the fact that she has the second highest damage (next to Kog'Maw) and has amazing mobility thanks to her passive and her. She doesn't require a really good team to peel for her, thanks to her condemn which lets her peel for herself. She is a good champion to pick if you want to carry your team.

This is just a typical mastery page. Vayne has a weaker early game so you grab the extra 2 points in the defensive tree to reduce the damage from the enemy ADC's basic attacks. She doesn't really need the final two points in the offensive tree because she does plenty of damage already.

I take the attack speed marks over attack damage because vayne'sare most of her damage, and you can get them off faster with more attack speed. If you are planning on going for a passive lane and not fighting then go for the attack damage marks because it will increase her poke damage. All the other runes are typical ADC runes.

I like to get attack speedon Vayne because, as I said before, she scales really well with it. In lane you often get bullied a lot though so I grab a http://edge4.mobafire.com/images/item/vampiric-scepter.gif to heal back the damage you take. Once you have your you just want to farm like a boss. You don't get the best damage until you build your . It basically triples your damage. I build a for sustain in fights and more damage. You want a before you build your last damage item because of how important you are in fights to your team. If you get caught out and die then your team is going to have a bad time. Your last item you can choose between a , (if they aren't stacking much armor) a , (if they are stacking a lot of armor) or a , (if they stack a ton of health) you typically won't need a because your already does a percentage of health.

In laning phase you don't have that strong of a poke, so you want to just sit back and farm. If you have a soraka in lane, a good poke is AA+Q+E to proc your, although it costs a lot of mana. In a drawn out fight though, you usually can output more damage than the other ADC because of your . Once you hit six, you can start being more agressive. You want to keep your farm high, because you will typically be carrying your team. If you know how to kite, you can often 1v1 someone who has full health when you have half. I have done this with a phantom dancer and a vamp scepter against the enemy ADC who was Corki, one of the top "counters." Your condemn is one of your strongest abilities. It lets you catch an enemy out, turn a fight in your favor, or even GTFO when the enemy jungler ganks.

Once you get into team fight phase, you want to stay a little bit in the back and basically damage whoever you can, preferably the enemy carries. You can damage tanks well with youras well. If someone tries to zone you, and your team doesn't peel, you have to kite them hard. Try to them against a wall and punish them. Also use bushes to your advantage. If you get the surprise you can out-burst many enemy champions.

Pros Cons
High damage Weak laning phase
Good mobility Squishy
Can carry a team Not easy to play
Has true damage

Vayne has a weak laning phase, and super strong late game. She can carry teams and does not require too much peeling, as she can do it herself. If you are good with her, you can beat enemy champions with much more health than you. She can kite very hard. If you aren't careful you can be killed very fast.
PS: If you want to raise your elo she is a very good champion to do that. I have a 70% win ratio with her.

Thanks for reading my guide! This is my first one so please don't be afraid to leave feedback.