How to control yourself towards toxic players.

So my 3rd game ever of ranked was pretty frustrating. I was jhin mid and was teamed up with two others who took themselves to seriously. All was good until they never listened to my pings and started to blame me for their deaths *which was their fault for feeding a jinx not even 7 mins into the game she was already 6/1. But anyways since my mid laner roamed they got mad at me for not roaming which i can see partially why. I never was told to roam and how to correctly roam throughout my normal games until these people told me. They could at least have told me in a informative way which would have been helpful. After all they are playing in low tier ranks what do they expect? I think these individuals were people who made second accounts to climb back up in tiers again. But after these two people got hostile towards me i couldn't resist but to tell them things back. After we got into a verbal war i couldn't concentrate anymore and did horrible the rest of the game and they made remarks about me saying i was the cause of the loss and pointed out my statistics after the game to everybody to insult me more. my damage was horrible towards the champs for this reason. When i only went 1/4 lowest deaths in team I have a tendency to fight back when i get heated up. How do i control my anger while in game? What should i tell toxic players who get hostile or hostile to others maybe in some cases? I am going to need it more than ever especially in ranked games.