Pay attention to which member of your team can destroy turrets fastest.
Try to protect them & get them fed then aim for turrets. Get turrets as an objective then...
Spam V-Pings on everyone to base if the enemy team has any chance of killing any of you.
Also, yeah, you may as well just start new accounts, I had 20 games in a row of people who fed & died like 45x in the first 10-15 minutes, followed by four-man-surrender-voting, forcing me to end up being demoted into Bronze twice in the fifth season, I mean, rather than playing through HUNDREDS of games just to climb out, better to just level up a new account with that kind of time instead.
Solo-Queue is MOSTLY about LUCK as far as I'm concerned. The last game I was the lowest-ranked, with four Gold-V's on my team, and four Gold-V's on the enemy team (and they had a Silver I), and somehow I managed to carry the shizzelnitz out of that game, especially considering how this season started off with EVERY single match after placements ending at 20 minutes in a four-man surrender-vote (occasionally for 30 fucking matches in a damn row !).
https://www.youtube.com/watch?v=CVctS6AgVqc&fmt=18
The Elo-System MAY be "mathematically sound" in THEORY but in PRACTICE it's TERRIBLE due to the fact that the amount of points you gain is based ENTIRELY on whether your opponents have more points for you to steal from or not (and the amount of smurfs causes a lot of inflation/deflation of ranks where I wonder how the HELL some of these people got their Gold-Borders whilst a lot of STRONG players somehow managed to get placed in Bronze/Silver).
The problems are also described here in this article (kind of like how to choose your opponents in order to have a maximum chance of rewards if you win whilst risking VERY FEW loss of points if you lose against chosen opponent)... https://www.thechesspiece.com/what_is_an_elo_rating.asp
Queue-Dodging & having multiple smurf-accounts is the only really semi-reliable way to not have yourself demoted from the troll-match-maker-system. One account requires a queue-dodge ? Not a problem ! Just hop onto the next one, and if it repeats, the next, and if you cycle through all of the accounts, then quit for the day, and that way you only lose 3LP instead of -10LP per subsequent queue-dodge !