If you can find out mindfully what causes that tension in ur speech apparatus (which is extremely hard to do and I would recommend practicing meditating to see when you tense, where you tense, that causes the blocks or I guess causes the resistance to your speech output then mindfully return to your breath when it gets ‘too much’ on your brain to continue resisting THEN repeat this over and over everyday like a religion, you may be able to just identify what it feels like when u tense and maybe find out why you tense like that. One thing that really helps no matter what is being calm (I know.. sounds impossible and some days it literally is BUT, something that really helps is to wake up in the morning, wait until your ‘awake and alert’ so to speak, and then just do a 45 minute deep deep breathing exercise and sincerely, you will be amazed at how calm you can be and how this influences your speech - but it’s like an art and it’s very difficult to not ‘get in ur own head so to speak’. Stuttering is very complicated but not something that should be radically dissociated from your being as all human beings have different capacities to communicating.