So about 2 weeks ago i dropped under 1000 elo and decided its time to climb back up. Now I realize 1200 isn't out of "elo hell", but its back to even so I consider it a milestone. So what was the key?
Well in my fall over the last few months from 1150 to 990 I tried playing a wide range of champs and roles, then I looked at my win rates with those champs. Some were pretty bad like 0/7 Janna, 0/2 Alistar, 37% jungle mundo, 40% soraka ect. Some were good: 67% support Zil and 70% Karthus. So I played a lot of Karthus and a new champ, Sona. I pretty much just took Sona straight to ranked as a main support so I lost an early game or two.
Now I've been winning about 70-80% of my games in this climb consistently. The best part is I'm using Sona as my first choice now. That's right 70-80% as a support. I don't have to carry my team, I just play well and we win. I ward well so bot rarely gets ganked bad. I can harass and heal. I let my jungler know about wards and pink theirs. Their carry screws up by hanging around with <200 hp pre-6 and I flash q and power cord them for a kill. After we take turret I ward the map for my team and buy good team items. Then I land a good ult in teamfights and spam spells and power cords. I don't have to lead to my team besides the occasional ping and hint. I win now more than when I played Viegar and started 4/0.
A second thing I've noted for when I play mid is that if I go in looking to win lane I often lose. However, when I get counter picked I sit back and farm and let them make the mistakes. Then I usually win. The mindset is to survive, farm and not screw up.
TL
R Read the whole thing if you want to understand, but play what you do well and you win.