reposting this from General Discussion as it's too fast there to keep a guide active. enjoy.

This isn't a guide on how to play AD carry and dominate games. This is a guide to help determine between you and your support which champions you can pick to gain an edge over the opposing duo.

First of all, I will try to generalize the different types of duo lanes that are ran bot. Typically, the duo lane falls into either a burst, sustain, or poke lane. These are bolded because any time you are deciding which ADC or support you are picking, they should be in your mind. The support champion chosen should enhance the strengths of the ADC bot. In contrast, if a support is chosen first, the ADC picked should synergize well with that support. Now, this isn't as concrete as I will make it sound, but if you understand the basics of this principle, you can evaluate at different periods when you have an advantage even if you were previously behind in lane. Lanes can shift from one type to another based on levels and often times they share aspects of each type.

Burst lane - A lane with high kill potential due to large amounts of CC and skill based damage.

Poke lane - A lane with low kill potential designed around attrition through delivering damage while avoiding incoming damage.

Sustain lane - A lane with low kill potential designed around sustained safe farming and recovery of health.

rules of bot lane:
Poke > Burst > Sustain > Poke

By picking outside of these rules, you are not guaranteed to lose your lane. Through outplaying an opponent, you can gain an advantage, but generally you will start disadvantaged by the nature of your lane.

Carries:
Graves - Considered mainly a burst champion through his high skill damage. Has some ability to poke with buck shot at the cost of sacrificing mana efficiency.
Ezreal - Depending on how you level your skills, falls into either a burst role or a poke role. Q first gives you sustained poke, while W will give you burst potential and a high mana poke. Maxing W first imo works better as it snowballs the strong early game. MIxed damage.
Tristana - Early game burst transitions into poke as levels give attack range. E naturally pushes waves which gives minion and level superiority in kill attempts.
Kog'maw - Long range poke with W. Even stronger poke at 6. High mana costs.
Draven - Poker I guess. Has a high early game kill potential. High burst with ulti in combination with all abilities.
Ashe - Poker with kill potential at 6. High mana costs with Q, volley spam, and ulti.
Corki - Corki is somewhat of a hybrid of burst and poke, but I think he falls more into a Poke role.
Varus - Strong poke and high damage early game. Can be played as a poker or a kill lane. Lacks mobility to follow up on high mobility champions for kills.
Sivir - Surprising amount of burst. Lacks mobility pre-6. Short autoattack range. Pokes through skills. Mana problems and high burst put her into the role of a burst adc.
Caitlyn - Epitome of a poking champion.
Vayne - Vayne works well in various lanes. She can kind of poke with tumble. High kill potential with condemn. Semi-weak early game.
Miss Fortune - High poke with Q. High mobility and attack range for sustained poke. I wouldn't classify her as a burst or kill lane champion but her Q does chunk pretty hard.

Supports
Soraka - Epitome of a sustain support. Can turn burst champions into pseudo-pokers through skill spam.
Sona - High burst potential. Lacks CC to initiate kills pre-6. Ability to poke. Considered a sustain champion.
Janna - Epitome of a poke support. Shield to give while mitigate damage. Ulti and Q can defend your carry while they poke.
Lulu - Kind of a more aggressive version of Janna. More kill potential due to hard CC.
Blitzcrank - Turns almost any lane into a kill lane. Tanky.
Taric - High burst. Armor aura. Stun. Kill lane support with some sustain.
Alistar - Alistar falls into a sustain/kill lane role. Sustain pushes creep wave. Bad at sustaining a frozen lane to allow carry to free farm.
Leona - Clearly a kill lane champion. Tanky with no sustain. High CC.
Nunu - Great for poking. Iceball harass in combination with a blood boiled poking champion. Move speed and aspd gives carry the ability to give more autoattacks while poking.

Basically, it comes down to picking a support and an AD carry that synergize with eachother. Most poking carries have high autoattack range or cheap long range skills. Most burst/kill lane carries do high front loaded damage through high mana cost abilities. Carries that work well sustain champions are usually weaker early game or have high damage high mana cost pokes (soraka allows these champions to poke)

If I left any champions out, try to think logically about how their kit functions and come up with your own description of that champion. Other things should be considered, such as healing debuffs to counter sustain, miixed damage to counter armor auras/buffs, and mobility to counter high mobility gankers.

example duo comps
Janna/Ashe - classic poke comp.
Nunu/Kogmaw - slow and bloodboil make Kogmaw one scary slug. Aggressive poke comp.
Taric/Ezreal (max W) - you pretty much instagib someone if taric stuns them. Burst comp.
Soraka/Kogmaw - ridiculous lane control at level 6. Sustain transitioning into Poke at level 6.
Taric/Vayne - kill somebody before they can even react with chained CC and burst. Burst comp.
Soraka/Vayne - safely free farm to reach hypercarry status late game. Sustain comp.

FINALLY, I want to talk briefly about summoner abilities. Pick summoners to either enhance a champions strengths or reduce their weaknesses. My preference is to play to a champions strengths and to be aware of their weaknesses. I don't think that picking a summoner will necessarily make up for a weakness.

Ignite - Offensive summoner. Great on strong early game carries. Don't take on support because you will kill steal your carry with it.
Exhaust - Offensive/Defensive summoner. Great on the support to protect carry and setup kills.
Heal - Heal baiting is infuriating. Ignite counters heal. One reason ignite became popular.
Cleanse - Cleanse counters ignite and cc. Basically you are nullifying their ignite at the cost of your own summoner early game. Great on late game carries with short autoattack range. Better late game in teamfights than ignite.
Flash - lol do I even need to say anything here?
Ghost - Nobody really picks ghost anymore on carries. Was popular when bot lane was an afk farm-fest to escape ganks.
Surge - I never use this ability. It might be useful on a champion like Kogmaw though.


SORRY This was so long. If I forgot anything let me know so I can add it. Goodluck guys.

Bump

Nice guide...LuLu definitely falls under Poke btw. She's basically on par with Janna. Both have a shield that increases autoattack damage, a long-range harass ability, an interrupt, a slow, and a clutch Ult with a heal and knockback.

And even though it's fallen out of favor, I believe Clairvoyance is still an important Summoner Spell to include for bot lane.

Lulu should also be able to work in Kill lanes, IMO. Even at rank 1, her W has just as much disable time as Taric's stun, and ranking her E for shield strength is a no-brainer, and also happens to raise it's base damage, too.

I think the main difference here is this:

Janna - Passive Poke
Lulu - Aggressive Poke

A Janna lane is typically more passive, focusing on wearing the enemy down with poke and stopping counterattacks with her shield. But she has the potential for a burst with a well-timed tornado, or a well-placed ult.

LuLu is similar. She can poke and shield almost as well as Janna, and she has the potential for a burst with her disable. But she's typically played much more aggressively early on. Putting a lot of pressure on the enemy, because her ult and disables give her more ability to set up kills than Janna.
Maybe this could explain why LuLu fell out of favor as a support soon after she was released; she falls between the typical categories of poke and burst, and thus is not as strong in either type of lane as the other supports.

Yeah champions don't fit one single role. Some loosely fit multiple roles while others change roles as they level.

I'm kind of biased to kill lanes atm. Most people seem to "get" that taric is a good support or graves is a good carry with early game burst, but they often times combine supports and AD incorrectly, so they get something dumb like Janna/Graves or Taric/Ashe.

Burst lanes reward proactive aggression and teamplay. They also seem to better support the idea of controlling objectives and early snowballing. Generally Burst loses to Poke, but all it takes for the burst comp to win the lane is to catch the poker/support once.

There are also a lot of odd combinations that happen to synergize really well.

Examples would be Soraka/Graves and Ashe/Sona (one of my personal favorites)

Soraka/Graves - The combination of their passives and the mana/health sustain allow Graves to use his Buckshot repeatedly and chip down the enemy; which made this a popular combination over time (but I believe Taric/Graves is much more common now that Taric has became the support FOTM).

(on second thought, this one is probably pretty standard, but worth noting: )
Ashe/Sona - At level 6 they have about a 3-second stun if they chain their Ults properly (Ashe's stun length is variable obviously, but you can average it out to around that much in lane I would think). The burst of the two ultimates, combined with Ashe's slow and Sona's speed aura makes it a near-guaranteed kill in lane.

On a side note, I played a match as Sona/Ashe against a Soraka/Graves, and Sona/Ashe absolutely destroyed them.

People need to read this post.

Many play AD and support without synergy and its why they fail. On the other hand people play champs with synergy but dont know how to abuse it.

You want to farm but at the same time if you have an advantage you need to make sure you shove it in your opponents face and constantly punish them for any mistake they make.

The difference between your team snowballing and the other snowballing is capitalizing on those tiny details and if youre bot lane is doing well then you know youre set for late game where your AD shines.