I’m mostly fluent now but I used to have a moderate-severe stutter. Speech therapy wasn’t a miracle cure but it certainly gave me ideas for techniques. I found a couple I liked that I built on. One was stopping completely then restarting with less tension in the neck, face, and shoulders. I personally have a big issue with hard impactful consonants like T or P, so I developed a soft onset technique. For example, altering the P sound to a subtle “Ph” (make the h very tiny). I treated using the softer impacts like a crutch while I worked diligently through things like dedicated practice and real-world applications through customer service and social situations.