Professional speaker Patricia Fripp suggests you use this speaking warmup to relax your face:
- Massage your cheek muscles with your hands
- Stretch the muscles in your face, moving your jaw up and down, your eyebrows up and down, tightening and releasing all the muscles in your face
- Move your tongue around the inside of your mouth while your mouth is closed, then open your mouth and stretch your tongue out beyond your lips while moving it around
- Recite tongue twisters (e.g., Peter Piper picked a peck of pickled peppers) slowly, then speed up
Tim Wilson
Professional Speech Coach
Free speaking tips at: http://speakingquicktips.blogspot.com