OMG, someone is on here being humble and not talking shit and blaming their teammates and talking about how they are God MOde?!?!?!? You, my friend, are what we need more of, and as a result, I'm gonna help you as best I can :)
First off, objectives over kills. This is so important. Your enemy will respawn, their tower will not. Have several champs you're good at, but have one champ that you are so good at that you'll pick it into it's own counter and still feel bad for the other guy. Be nice to your teammates, they want to win too. Be nice to your enemies, and don't let them intimidate you. Understand who you need to focus, and do so in fights. YOu said you usually get carried? I have a strategy for that too actually. Shadow the guy who's whooping ass. He's going to most likely keep getting kills, and you can jump onto the assists for the gold. Last hit cs last hit cs last hit cs. Understand the flow of lane stalling and pushing. Play ARAMs. They'll make you teamfight like a boss. Do not commit to a single build every time. Commit to the idea of counterbuilding your opponents. There are some games where I won't even build the core item because the core item will not help me in that particular game. Best thing I ever did as far as securing ranked wins go though was picking up Sona and learning to support like a fucking monster. Usually the support is there by default of the other roles being taken already, and they aren't as familiar with it. Sometimes they don't even like it (new champ select makes that more rare). If you are able to support well, not only will you know that your support stands a good chance of doing well, but so will your ADC. It also means that you've rejected two people on the enemy team instead of one. There's honestly no right or wrong way to carry. Most of it comes from finding your style and learning how to manipulate it. It's also important to remember that you can't win every game, and that that is no one's fault. Five people will win, five people will lose. When you lose, be happy that the other team was able to get a win and taht they are happy about that. This will keep you from getting worked up in your head and making bad choices later. Just remember, this is a game and the highest priority is to have a good time and enjoy yourself........also, this one is a bit more devious, if one of the enemy players is foolish enough to get onto /all chat and complain about his teammates, that's a rager. The first thing you do to a rager is focus them every chance you get. Go out of your way to hunt them down. They'll get mad, blame their teammates, and throw the game. There are several bronzies who are stuck there because they react that way. While it is kind of mean, it is very effective. Besides, the guy is being mean to his team in team chat almost every single time so it's a taste of his own medicine....oh yea, don't type a lot either. YOu should only type when it is crucial but pings can't explain what needs said or you are dead and waiting on the respawn, otherwise it could get you killed.....same in reverse, if someone suddenly stops moving, they're typing, destroy them.