Take a picture of your resting face or look in the mirror and see what adjustments can you make. Practice your expressions at home, develop control over the face muscles. Lifting the corners of your mouth makes you seem happier. Lifting your eyebrows a little helps to get rid of a tired face expression, fully open yet relaxed eyes look most inviting. Relax your jaw and your tongue inside your mouth to soften your facial features. Lastly, you can tone your face muscles by doing head, throat exercises like practicing OM chanting, pranayama yoga, and playing wind or rhythmic instruments.