Just like other professional folks who speak for a living we need to warm up and get ready to perform!
But how? Here are some tips that I use and they might be helpful to you.
VOCAL/ PHYSICAL WARM-UPS FOR STORYTELLERS AND SPEAKERS
Inhale through the nose, exhale through the mouth. Do this 5 times.
Inhale through the nose, filling lungs to 90% capacity, then quickly fill up.
Exhale with a relaxed a-a-a-h. Do this 5 times.
Stretch your neck to one side (ear to shoulder), then the other. Do this twice.
Stretch your chin to your chest, then back. Do this twice.
Stretch all the way around (chin to chest, shoulder, back, and chest) 5 times each way.
Shake all over, like a wet dog, starting from the top and working down.
Say "hah," "he," "hi," "ho," and "huh" from your diaphram.
Say each of your vowels from head to toe, toe to head, as if the sound is coming out of those parts of your body.
Say each of your vowels as if it is coming from you mouth only, then nose, then eyes, then top of the head.
Say each of your vowels from your facial mask ( your whole face).
Say "b-r-r-r-r" as if you are a race car. Do this several times.
Say "guttah buttah buttah guttah, good blood bad blood, good blood, bad blood red leather, yellow leather, red
leather, yellow leather"
Say "The Swiss wrist watch sank swiftly" 5 times.
Of course you might want to do these exercises somewhere by yourself!