I've had a few people I've met in normals add me and asked me what they should be learning from ranked and I think overall this could help even people who have played ranked before. So here goes.
Starting:
Don't focus on one role. Be able to play ALL roles okay. Obviously you're going to have your favorite role and least favorite. No matter how much you hate it get good at a few supports. I've found that people who hate playing support pick ones they aren't good at it and basically costs the team the game. You're not going to get mid every time and saying "mid or feed" does nothing for the team or yourself.
Don't focus on snowball champions and learning how to play them. While they are fun, they are banned at low levels and you just waste your time trying to learn them. Learn the staple champions and you will be fine.
Pre-Game:
Always know what you're going to buy first and where it is. You should never be in fountain after 20sec on the game timer. The longer you take to get out of base they deeper than can push in w/out you knowing. This also works when backing. You should know what you're going to buy as your backing, the longer you take in base the more CS you miss and potential team fight damage you miss out on and could cost your team.
Lane Phase:
Focus on CS not harassing at the start. Giving up first blood 2min into the game is never good, while you may think that you can get it and it will be massive for you. The risk is way too high for the reward. Play it safe and just wait for your time. A gank from the jungle is more likely to end in a kill than you going in 1v1.
As the jungle don't waste your time trying to gank lanes that are shoved. Inform them that they need to freeze the lane in the middle. The more time you spend trying to gank the less time you have to farm. The less farm you have the less effective each gank will become.
As support you want to harass the adc or support as much as you can w/out being to agressive. This will allow your ADC to farm with ease and will ease some of the lane pressure. Remember your job is to keep bot lane safe for your ADC. That means warding and counter warding. The less harass your ADC takes the more successful your late game will be.
Mid Game:
Objectives > Kills. This shouldn't have to be stated but I feel like it must. You should always go for objectives rather than chase down a kill. The more turrets you destroy the less pressure the other team can apply on the map. You should strive to have all lanes pushing onto their side of river, not yours. Prioritize killing the bot lane inhib first as it will make baron defense and taking baron a million times easier with supers pushing into their base.
While team fights my decide the outcome of the game. The lost factor in all that is the amount of turrets taken prior to that. If you lose a team fight but all their lanes are on their side of river. There is a chance that you might walk out of it just losing one turret or maybe even zero. So remember, a turret taken is worth more than one kill.
Late Game:
As always late game usually ends with a bunch of team fights. They are one or lost in the matter of seconds and the key is to not hesitate. Your team needs to decide if they are going to go in or not. Any indecisiveness is weakness and will lead to a lost team fight. If somebody gets caught you either go in or back out right away. You can't wait a second or two to make up your mind. It has to be right away. I've seen too many times in fights where a person looks almost lost because they don't know if they should back out or keep fighting and end up doing nothing for a second and in that second they could have either gotten away or turned the fight around.
Most importantly. NEVER GIVE UP I can't tell you how many times I've been 1/6 2/8 and ended up 15/9, or had both nexus turrets dead and came back and won. No matter how far behind you are you still have a chance to win. They key is, don't force team fights and be positive. Just push lanes and keep farming and you will catch back up. Teams tend to get cocky and will stay around later than they should with less hp than they should and you can take advantage of that. Late gem rez timers are quite long and you can easy baron/turrets from it.