I need help...

I have been playing League for almost 2 years now. I find the game really fun but as I play more and more I see myself becoming more and more toxic. I have gotten 4 chat restrictions and have just been banned for 2 weeks. I do not enjoy being toxic and since my first restriction I have attempted to prevent my toxicity. I have tried writing rules near me to look at if I get tilted, and I have tried muting people. Most of the time my toxicity comes from arguments with other players or flaming teammates that have fed or flamed other players. I wish to stop and I am at the point that although team chat is important I will be muting all from now on when I get into games. If anyone has any other tips or anything to help prevent toxicity, please share so I can end my harmful habits.