Anyone know how to manage this type of stutter

Anyone know how to manage this type of stutter I’m gonna try and describe it the best I can ,my stutter is when I want to say a word my lips kind of press together and the words can’t come out and I kind of look funny,I have a speech in about 4 days and I’m freaking out,I know one I think I should do is talk slowly but when I’m nervous the stutter goes crazy,any help?