Does anyone know some effective relaxation tehniques??? (I need to presentate by tomorrow!)

Does anyone know some effective relaxation tehniques??? (I need to presentate by tomorrow!) So I have a pretty bad stammer, especially when I need to presentate something. Tomorrow I will have an exam which involves a 10 MIN. presentation! I'm pretty fucking stressed, like it's going to kill me. Basically do you guys know some trick that makes you stutter less while doing things like presentation? I'm really desperate :( UPDATE: presentation went much much better after following these tips! To people who are unsure about these amazing tips, it really does work! Upvote this so everyone else can see it, cheers ;)