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.
TLR Read the whole thing if you want to understand, but play what you do well and you win.