So... The role I am most comfortable with is Support, but lately I've realized that Supports ain't s*** without a team that knows what they're doing.
For example: ADC constantly pushing so Jungler can't gank, Top treats their lane as an island and rarely helps, etc., etc..
What is a way that I can improve as a player and carry games? Should I only play ranked? Are players more serious/careful in ranked (I am currently unranked, but I'm pretty sure I'm Bronze)?
When my ADC is acting like a duffus I try to actively help anyone else on my team. My first choice is always the jungler because they are moving around the map ganking other lanes so me getting my jungler fed indirectly feeds my top and mid laners as well. And maybe, just maybe, doing this can help pick my ADC out of the grave they dug themselves into.
And you can help out your jungler by simply warding things for him. Ward dragon, enemy red/blue buff or even pink warding his jungle to prevent invades. If the enemy jungler is an assassin you should assume they are going to try and invade on you so when you ADC dies because of a level 2 cheese just back, buy a pink and place it in your own jungle somewhere.
Just spend alot of time playing the game. At lower elo its actually better that the adc pushes the other adc and support at their tower. What this does is that it makes the adc miss the CS because the tower will deny him the cs kill. at bronze level not alot of people know how to farm under tower nor does the jungle know when to gank. Furthermore, not alot of players in bronze know how to RECEIVE the gank properly anyways.
Main jungle then :D just learn
Players might be a bit more serious in ranked, but its not utopia. Far from it. I'd rather stick to normals for practice.
To carry a SoloQ game, for me the most important thing is honestly to rally your team around you. Being successful, killing an enemy or taking an objective, it does quite a bit to raise the morale of your allies and give them confidence to play around you. This is the easiest way to bring a team together as a team in a soloQ game. This can be done from any position. I've carried games with one well timed teleport bot from top that net me a double kill, and from there on my team let me lead. I was a tank, and when I initiated, they followed. It was all I needed.
From there, you need to be able to play with your team. When you're successful early, you can get ahead and snowball, but if you try to solo too much you'll often get shutdown. Your opponents will take notice of your success as well. Mostly, this is just about grouping with teammates, and having the map awareness and positioing to not get caught out. Then, even when you have games where the entire enemy team will die to kill you, your own allies get the gold off of this and will probably continue to be happy.
The best way to get into this leadership position is really kills. They're announced to the whole team and generally emblematic of success. It doesn't necessarily have to be in the early game but usually the earlier the better. And of course, there can be still be people who will hate you regardless.
I'm stuck in a similar boat as you and I've found success playing supports that can potentially (and easily) be turned into carries. I've been playing 
and 
lately with some success.
I've also found roaming mid lane to be helpful in getting a snowball started. If you do intend to roam, however, make sure there are plenty of wards to keep your ADC safe while you're gone.
Like others have said, stick to normals when your starting out with a new champ/role. I find Team Builder to be a great place to start especially since you pick your role and champ before queuing, that way you get exactly what you want. Down side to that is the team comps aren't always ideal.
Sweet. Thanks for the advice everyone.
get better in general for support just play soraka and win with positioning and heals or leo with all in engage potential and make plays on carrys super easy. I dont play support often but when i do i win
Play every role so you can understand many of the champs inside out. You'll probably pick up some new mechanics/tricks by playing all the roles too.
