The following vocalese will set a good foundation for the rest of your preparation to wing well. You will hear the sound of a vowel you are to sing. Then will follow a scalewise exercise up a fifth and back down to the starting note. You will do the exercise on seven vowels. Then you will move up a half-step and repeat. You will repeat the exercise seven times.
The goal is to keep the throat and mouth as open as possible. Always take a good breath and seek to maintain the purity of the vowel throughout each phase.
Vocal Warmup 1