I want to improve better on ranked.

Hello! I am a hard stuck Bronze player. My main champion is Yasuo. Now let's get real here. If you look at my match history from like 9-12 days ago you can see I was playing really good. Now, my match history from this week I've been playing horrible. Ever since I got promoted to Bronze 1 I've been playing horrible. And I want to change that. I'm not asking for a coach (although I could need one some time like right now) but I want to improve on my own. My CS is good! Okay, so for short.. I want to get out of bronze. This is probably the most frequently asked question but I want some information off of a Diamond 2 and above to a Challenger player. I know the season is already over and we're in Pre-Season but I still want to get out of Bronze. I'd recommend to look at my match history (recommend OP.GG). If you look at my match history to where it starts to be pure Zed and Yasuo games you can see I was doing really good. But now I've been doing bad. Almost everybody is flaming at me now in-game lol which I think is funny. But anyway, I need help on how to get out of Bronze. Information and help from a Diamond 2 and above to a challenger player. Thank you if you read this. I really need help. Also, this could help me on if I'm still in Bronze in Season 8 so don't act like "this season is over anyway, just wait for placements" no.. help me. plz.