For me it was repetition. Stopped all my jerks and attempts to guide it out with my body so to speak.  The harder I tried, the tighter it got and when I was too tired, the moment of weakness was when it finally came out so many times back in the day.   So I stopped forcing so hard and tiring myself so intensely.  Instead, I repeated until it randomly just came out like any other word all of a sudden.  I wasn't mad at myself if I wasn't patient enough but the moments it worked, it shocked me that I didn't have to fight it with all my might (leading to the jerks and movements and so on) and over time my body and mind got used to it.