Hi! I've been struggling with the same problem, but I've learnt how to slightly avoid stuttering. This is based in personal experience; doesn't have to work for you. I grab a pen or a pencil and start to beat a constant rhythm, as if it was a metronome. Then, I start speaking by the beat, not skipping any beat, but maybe accelerating. This helps me regulate my speed and I do so much better. The other suggestion is to do muscle relax or to relax the larynges area before the presentation (you can search some up). This could be done by Jacobson, voice exercices, etc. Relaxing larynges area makes your probabilities to stutter significantly low, since your vocal chords are better prepared.