so i just bought vayne today and played two rounds with her. HER DAMAGE IS INSANE and i carried both games. but shes so squishy and gets bursted down so easily when people focus on her. any tips on how to stay alive .____.?

Don't initiate any fights
Watch out for oracles or lee's E
Get a GA
Get Banshee's veil if you think stopping a spell will help
Get mercury treads for reduced crow control effects

if your getting focused use your ult/tumble to get some breathing room.

-Summoner spells, Take flash or Ghost (I prefer flash) maybe a heal if your support doesn't have one.

-Q!!!! Tumble is great for dodging skill-shots like Lux/Morgana bind or Orianna's balls... (Takes some practice)

-Make sure you have good positioning, Positioning is EVERYTHING so think about where you are.

-Never initiate team fights...that's your tanks job.

-Consider grabbing a Frozen Mallet. With a Phantom Dancer, I.E and Frozen mallet you have good attack speed for kiteing which means you can escape from sticky situations: Ult>Tumble>Auto-attack, gives you nice distance as well as slowing the enemy. Continuing to kite allows you to take less damage as well as keeping them slowed. If it's a 1v1 fight and you get them low enough to kill then turn to kill but remember you're RANGED so don't go balls deep till the kill can be secured.

-Boots...I sometimes like to grab Boots of swiftness when you've finished your build you'll hopefully have a phantom dancer or two...so there is your attack speed which means you don't really need berserker's greaves. With Boots of Swiftness+Passive+P.D+Frozen Mallet you have amazing kiteing capabilities. When you press R no one can escape and YOU GET KILLS!!

Hoped this helped

Back to my classwork now :/

If you don't want to sacrifice damage for survivability then you just have build like a squishy and act like a squishy. Since she is a close range ADC, your team should be aggressive to get you in range.

If you are in trouble you will have to resort to leaving the fight, resulting a likely defeat of your team, but it's better than 4 die than 5.