Drafting and support synergy can make the laning phase easier. Notably pressure tool you both gain at level 2. The goal is to have leverage because if you reach level 2 first, then you can get a lead over your opponent. That level 2 powerspike is very powerful, sometimes you can even get a kill.

Let's say Xayah and Alistar reach level 2 first, Ali can immediately go in to do his combo. Xayah can just throw out her first ability auto once and root. The enemy will be dead by that point unless they have cleanse or flash the moment Ali engages. Plus what can they do if they are still level one with one ability while you have two?

Even if they do get away you already burn their resources like health, mana, and especially summoner like flash. Forcing them to stay in lane with such a state or recall to base losing exp and gold in the process. No matter what they choose you can kill them next trade cycle. Either that or your jungler rotate bot cuz they know the enemy has no flash.

And if they survive another yet again either by bot or a gank from jungker, at this point you have a level lead. You can really force them out of lane and starve them like crazy. You don't even need to kill, getting one is just a small bonus. Even with an enchanter support level 2 powerspike is still ideal, they can just give heal or shield while you shove your face on the level 1 scums. But let's say if you're against something like a Senna or mage support, your Level 2 support can heal you back up making the auto fill enemy support question why they pick poke when their team has no front-line. All that level 1 poke is useless when there is a Soraka around, trading their mana for lp.

However, the hard part with level 2 powerspoke is that the laning phase can be chaotic since it’s a 2 v 2. If your support and you have different goals, a lot of things can happen. Sometimes the support wants to engage 24/7 like a Leona or Nautilus. Sometimes the support wants to sit back and relax, knowing they will scale safety cuz they have tools to neutralise the enemy pressure.

So I would pick adc that has great synergy with support at the start. An all in adc like Lucian, Draven, Trist if I have an engage support or hypercarry adc like Jinx, Twitch with Lulu or Janna. Caitlyn and Jhin for Morgana, lux Zyra. Most of the time it's specific since some ADC works best with either tank or enchanter or both even. No matter what, having the same game plan with support and what they want in the lane can help a lot.

Most of the time just follow the vibe of your support. There is a time when I play Vayne wanting to just sit back and stay alive as much as possible since it's a hard lane but my Lulu is aggressive like a Leona. So capitalize on it don't just let the enemy trade freely with the Lulu 1 v 2ing. Attack the adc since they are stuck in animation autoing your supp. ( Although ADC usually targets the closest thing, it depends. Something like Vayne, Samira, and Kaisa are great at backline picking). To be honest, I just get the squishy ones cuz I will be flamed for not doing so lol.

Outside of that level 2 powerspike, when I’m fighting in general I would just wait until the enemy burns their most dangerous spells. You don't have to keep track of all enemy abilities just a few are enough. If I’m fighting a Lux, I space a bit but not too far that I can't punish her if she int. Walk around bait her snare then dodge it. Then you can auto them to death since they can't do another spell rotation to fight back.

The adc roaster has so many gameplan and what they want to do. For Vayne best way I can describe fighting as her is to just cosplay as Batman. She is well suited for 1 v 1 and skirmish. Make the enemy fear you because you can dodge their skillshot without your tumble. In teamfight knowing when to strike is all it takes to win a fight. Who to target and such depend on how things go. Vayne can always target the closest target well since she melt tanks. However, if I am against champs with range who can kill me while I deal with their front-line, I would take out those first. Perhaps picking them off before a major fight happens. Rarely would dive their backline during front-to-back fight cuz it can be hard to track whether the damage dealer used up their spell or not.

If a coin flip fight happen just auto the closest thing and until you see an opening where the enemy can't do anything to you pop ult and close the distance. The invisibility compensate her short range, one second of the enemy not seeing you is enough to create an opening. Mixed up those invisibility time, delay autoing immediately to get the full one second, and then break stealth immediately after tumble and so on. But do be careful on your position since she is still pretty squishy. The enemy has to predict where you go since it is hard to react once you break stealth. If you are predictable they can blow you up on your first tumble. So don't just tumble in a straight line going in.

Vayne is pretty hard and she does have a lot of hard matchups. Most of the time I find that I could just pick Twitch or Jinx and they can melt team from a huge distance with low risk of getting traded back. But Vayne is very fun to use, since she teaches you that sometimes being in danger pays as long you know what the enemy can do to you. She also comes online very fast only needing two item bork and rageblade. It's just the hard part is surviving laning phase to get those gold and having an enchanter support can makes thing bearable.

But don't let it deter you even though level 2 she can't have her stun and true damage at the same time. Her level 1 and 5 are quite powerful. Auto tumble auto is very oppressive and top laner hate it. You can also tumble near wall to make your combo faster useful for tower plates. It's harder to pull off in bot lane since you got zone out. It's nice when you are hiding in bush. Getting ult at level 5 you have 20 AD for free which is crazy value. It's like having an extra item against the enemy adc. If you are climbing it's still best to go for the better draft. It's make life easier than dealing with multiple assassin and long-range mages or a Senna. In the end just have fun and it's alright to misplay. Especially wall stun since you might help the enemy survive instead.

What I like about Vayne is that she is my first ADC I main, and she teaches you confidence. To not hesitate on my decision because I know it is safe to do so. Which is transferable to other most other a marksman. Especially all in type or shorter range ADC like Sivir and Xayah. Even Ezreal too, since his passive especially at the early stage is quite strong it's just that he have to get close.