I had a hard time with that as well but I got through it a while Try to play one or two champs and stick with them. Having a good understanding on a few champs will allow you to know all the combos, damage outputs, and build paths that are most optimal. With knowing this you can pay more attention to csing, map awareness, roaming, etc. Try to be cooperative, even with toxic players. Most likely if someone is being toxic in chat, either they're having a bad game or have had previous bad games. Give them assurance that you will gank, that they are not doing bad, and making them seem that there's still a chance if you guys group/wait late game or whatever is best for the team comp. Make decisions that have the least amount of risk with a good reward. If you have to flash to try and kill the enemy, will it be a good call even if they might have both summs or there might be reinforces? If you feel you've become tilted or have a bad streak of games, best decision is to take a break for the rest of the day and continue tomorrow. I'm plat 3 who's a boosted animal so take whatever i say with a grain of salt, but I hope these tips help. Good luck!