Simply put those who believe in ELO hell are bad at math. =)

First of all, relax. like seriously man, go outside and breath, stay quiet and chill.

Are you back? Good, are you relaxed? Good.
Now, i was at 900-1050 elo range last season, this season im 7 games away from silver and i was 2.
How do you win games?, how do you carry teams?, how do you become a better player?

1.-Keep a mindset that a win or a loss in a single game it's not good, a positive W/L Ratio is a good.
2.-Do anything but support until silver, 1250 and below is where supports are not really appreciated.
3.-Learn all roles and learn 3 different champs on your 2 main roles and 2 champs for the other 3 roles.
4.-DO NOT RAGE, Raging, telling someone they suck, just saying every mistake at someone won't make them play better. They derped around and got killed, well don't be aggressive, don't be a ****** bag, say something like "Relax, it happens, be careful and next time do x thing"
5.- Learn who to focus when and in what instance.
You have a late game carry, play protect the carry. You are ahead and got a mid game garry, focus squisies. There are a lot of scenarios, just learn to read them.
6.- WARD, IM NOT ASKING WHAT ROLE ARE YOU...WARD.
7.- This might be the most important thing i can tell you : Do not blame your team for your loss, do not blame the enemy team, do not blame riot and his system, blame yourself, why? See your mistakes and fix them, that's the only way to get better and improve.

Good luck =3

Two, not one

Play support more. If you are good at the game, it is practically telling your team what should be obvious. If you can carry as support, then you are probably better than your ELO says.

Dragon up at X. OR/OB/TR/TB up at X. Peeling for ADC that normally wouldn't have a peeler.

Enemy jungler starts at X and gets to top/ bot by Y. If they are over extending when the enemy jungler is coming for them, ping them back. Zone for the ADC in lane and poke without dying.

Learn the warding spots. Call the wards+ timers. Pay attention to ults+ skills used, abuse the fact that those skills are down.

Watch the minion waves. Are you pushing before you B? Are you making sure not to push with the jungler near bottom? Are you initiating with a minion wave advantage or disadvantage?

Know when objectives need to be focused and let the jungler know. Look at teammate item builds and tell them what needs to be improved. Look at enemy stats to figure out their rune setup. If you are high ELO worthy you should know what runes the person has just by seeing their stats (for the most part).

Predict where the enemy is as where you cannot see.

Know the skills of all champions. For example if you play Nami with Caitlyn and you watch her passive meter by clicking on her, you can E her the second she gets her charged shot. Remember 20 damage is a TON of damage. It may be the difference between a won and lost lane.

If you know your champions, let the team know when they are countered and give suggestions of how to survive/ deal with the enemy before the game starts.

Listen to Thorston13 (2 posts up), he/ she makes some good points. I disagree about the supporting factor though. You play a much smaller role, but your role is much easier and less ADC dependent. Nothing is more enjoyable than not having to worry about an enemy warding! ^.^

Why is this an argument? Since when is there an I in team? Why do you have to do all the work for your team or you won't win?

Sure statistically the better players will win more often, HOWEVER its easier to fall down a league than it is to go up + the amount of games you have to play in order to get up to the next bracket will take week. Also you have to consider the psychological effect of playing with complete ******* which will lower morale and thus lower your playing abilities. Sure you can climb out, the question is how long will it take?