Like, don't plan extensively or sit and think about it. Like what I did was whenever I had the urge to speak and that nervousness or the thought came in, I just stopped and thought once what I had to say and just waited for an opportunity to say it, or just try to speak my part, no matter how small and when I started, I just said stuff like " hmmm, not true, I agree, really?", just small stuff that would just help me get over the fear that I will completely stutter and get insulted or embarrassed. Like after that, it was just me getting used to doing that. Also approaching someone you really want to talk to or someone u absolutely dread talking to is the best way to get super fast progress. Cause after that it's like everything else is less "high-stakes". Like small conversations, don't get too angry, jumpy, or excited. After that, it's like letting go of the clutch of your vehicle. You let go slowly and u see the car going forward and u just let go. Be nice and be kind to yourself too.