How can I raise my MMR before the system drags me down to Bronze?
So I've been low gold the past two seasons, went 4-6 in my placements this season and got placed in Silver III. Not the best, but no big deal. I can grind my way up. Well I got this crazy idea that I can play Cassiopeia even though I hadn't touched the champion since season 1/2 and because I wouldn't give up on it and because of a few leavers/ragers/disconnects what-have-you, I went on a ten+ game losing streak and now my MMR is in Bronze 2/3.
I'm in Silver IV.
I gain 10 LP for winning and lose 25 for losing, making it functionally impossible to advance with anything below a 75% winrate, and I'll be the first to admit I can only pull a winrate like that on one champion. Who I play as often as I can already. So despite going even in wins/losses, and despite my current 88% winrate and 4.6 KDA on Morgana, I'm dropping leagues because I can't win enough to overcome the +10/-25 that I'm facing.
On top of that, I have no idea how to play in Bronze. I'm not used to the way people play down here, so does anyone have any tips to getting my MMR up out of Bronze before I actually start playing the way people down here play and become worse at the game than I already am because of the people I'm stuck playing with/against?