Trygelan's Tips, General thoughts, Strategy and such.

[Kaden]

AD Bot - Kaaden can probably add more to this than I can since this is my weakest role, but I do have a few things to say.

Farming is absolutely the most important thing for the AD. If you're playing the AD for your team, it should be on you to make sure your mechanical skills are as good as they can get. In most cases, the team is going to be depending on you to do as much sustained damage as possible, but that's not much help if you don't have the items to back it up.

For Summoners base what you get on who you pick and who you're lane partner is. A good example of this is a Tristana/Janna lane. Tristana is the safest ranged AD with her combination of range, blink, and targeted knockback. Combine that with Janna's kit and you have a very hard lane to gank. In that situation you could definitely forgo Exhaust or Ghost for a spell with more utility. (Honestly you could probably get away with not taking Flash, either, but it's just too good of a panic button not to take. Right now there's no reason to no reason to not have Flash for competitive play.)

If you're playing Ashe, MF, Sivir, or anyone else with basically no escape, you pretty much have to run Ghost/Flash. If you have a support that is incredibly good at keeping people safe (Ali or Janna are good examples) you can probably run Exhaust instead of Ghost, but even then know that you need to be hyper aware of your positioning and how exposed you are to potential ganks.

Try to play with the same couple of people as consistently as possible for your duo lane. Good coordination can mean a lot more than individual skill. Take a look at pretty much any game with Nyph and CandyPanda and you'll see some insane laning. It's a lot more like they're playing one champions with eight skills than anything else. Barring that, though, just try to be aware of your lane partner's positioning.

To touch on what Tryg said about starting items, take your runes/masteries into account for lane set-ups as well. I suggest boots/pots as the default start for most people (movement usually lets you get some extra harass and pots explain themselves) but don't be afraid to play around with that. Doran's + Offense lifesteal is pretty potent. Most people probably wouldn't call HP5 quints ideal for Ranged AD, but if you have a Janna, for example, then you can make up for the loss of early game AD or ArPen.

Ultimately, your job is to sit in a lane and farm, farm, farm and then come to a fight and do tons of damage. You don't need to kill the people in your lane (obviously don't turn down a chance to) and you don't need to roam around and gank. Just farm. Take whatever runes, masteries, items, and summoner spells that will let you do that as safely as possible.

In team fights, positioning -- and the associated combat awareness -- is the most important thing to a ranged AD. Ghost is absolutely fantastic for this. Pop Ghost towards the beginning of a fight and use it to kite in and out of a fight as often as possible. Hit the highest-value target you can safely get to. While you want to kill their most dangerous champions first, it's more important to constantly be doing damage. If going for a squishy means you step into range of a mage or a bruiser, then it means you were targeting the wrong champion. (PLEASE NOTE: THIS IS BEING SAID ONLY ABOUT RANGED DPS, NOT ANY OTHER CLASS. MAGES, FOR EXAMPLE, SHOULD NOT FOLLOW THIS GUIDELINE AND WASTE COOLDOWNS ON TANKS BECAUSE THEY WERE CLOSE; SAVE THAT SHIT FOR THE PEOPLE THAT NEED IT AND LET THE SUSTAINED DAMAGE DO THE REST.)

When something targets you, it gets outlined in orange. It constantly surprises me how often people don't seem to know this. Be aware of it and use it to your advantage. It will tell you when you pull tower aggro even before the targeting laser hits you. It will tell you when that Xin is running towards you so he can get in range of his dash. It will tell you when an entire team focuses you and you need to Flash the fuck out immediately. Be aware of it.

The only thing I'll really say about builds is to always prioritize early DAMAGE over early attack speed/crit chance. Berserker Greaves are cheap and give you enough attack speed to get through the first 20 minutes of a game. Yes, Zeal is also cheap, but just because you can afford it doesn't mean you should buy it. AS and Crit are pretty much worthless if you're sitting on 71 AD.

So, to summarize:

Laning: farm, always be aware of people's positioning, farm, take whatever items/masteries/runes you need to keep you in lane so you can FARM.

Team fighting: consistent damage to the highest-value target you can safely reach, be super aware of your positioning (if you need to hold spacebar for a fight to keep track of yourself, do it!)

Items: early AD > early AS/crit