Also practice talking to yourself and pretend that you are taking to someone else as well it helps with commentary if something is frustrating say what it is and why. Pround of a achievement the yell or do something to show it. You could also talk about yourself or things that happened to you recently that you find amusing while playing a game. Its like a vlog/gaming commentary. One of the best ways to do this in my opinion is to record your gameplay without audio and then dub over it later. That way you wont get to distracted with playing the game and going silent.
I hope this is of any value.
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