I like to exercise my facial muscles from time to time.

Close your mouth and bring it forward as if you were kissing.
Suck both cheeks deeply into your mouth so that the ball is swollen.
Then, roll your lips inward so that they are not visible and stretch your lips to the sides with water.
Inhale and slowly lift and protrude your lower lip and chin for 5 seconds.
Circle the muscles under your lips and hold for 5 seconds.
Slowly return to a natural expression for 5 seconds.

Repeat 5 times. Exercising your facial muscles regularly will make them firmer and more elastic.