I fell from S5 to B5 in a matter of a couple weeks, but that was entirely my fault for wanting to play different champs and builds. Having learned from my mistakes, I know that to close games in bronze (for me at least) is to play AD melee champs with gap closers. Chances are the enemy is just as bad at grouping for objectives as your team is, making it relatively easy to catch enemies out of position.
I kill priority targets then push a wave to turret and take it.
I place minimal value on farm because farming requires an excessive amount of time, time that could be invested in eliminating another target. I can easily return to farming and level up once or twice with little effort as the game progresses if I fall behind in level.
I avoid playing support, ADC, AP, or tank. Support and ADC is a trust exercise and I have no trust for any of my allies; in fact, I hate my allies...I hate most people on this planet (I especially hate the four idiots at the sandwich shop earlier who told me they didn't know how to make a tuna salad sandwich from their menu!)
I don't bother with tanks because they're just inconsequential meat shields for the carry and the carry in bronze is unlikely to perform optimally.
And forget AP, AP can gobble up enemy champions, but then there's that exposed enemy turret you're hitting for negative damage while your allies are all "well, okay, that guy is dead, let's go back to base and wait thirty freakin seconds to finish that next item"
So, yea, you want to crawl your way out of bronze then try picking one of these.
