For me it helps to speak with my hands. I also have a stammer (blocks) and for me there are a couple handy tips: 1. BREATHE at every start of the sentence, dont push words out. 2. Make the first sound of the sentence a bit longer. Try this. It helps with the rest of the sentence. 3. Move your hands at the speed you talk, when you feel a block, guide yourself with your hands. You also seem more enthusiastic. 4. Try to keep yourself from pulling funny faces. 5. Slow down, no one is rushing you. Keep in mind these things work for me, not necessarily for you, practice a bit before hand, maybe read a couple pages out of a book out loud. Good luck!