How to form your mouth for the best flute sound.
The lip plate should rest just below your lower lip. The edge of the embouchure hole should line up with the edge of your lower lip.
Form your mouth as if you are saying the word 'pooh.' This gives you a good starting shape for your embouchure.
The opening between your lips should be small and focused — about the size of a grain of rice. Too wide and the sound will be airy.
Drop your jaw slightly. A tight jaw creates a thin, pinched sound. A relaxed jaw allows for a fuller tone.
Embouchure development takes time. Your muscles are learning a new skill. It is normal for your lips to feel tired at first.