- Don't type when you're upset.
- Don't spam pings because you aren't typing.
- Don't intentionally feed.
- Don't intentionally withdraw your presence from the team fights because you're upset.
You just have to bite the bullet. If people are being toxic to you, take the high road. Ignore and mute them. Just play the game. If it's going poorly, take the game as an opportunity to practice mechanics and practice assessing situations rather than playing to win.
When you have a cooperative team, that anger doesn't come out. Sure you may get frustrated when you make a mistake, but EVERYONE makes mistakes. Even the best pro players die. Even the best pro players miss farm. Even the best pro players get their jungle stolen.
Also, play with friends and have fun. I have SO much more fun in SR with friends than I do with 4 randoms.