As someone who used to have an insane unideal facial (and body) symmetry, sleeping on your back and doing some facial massages will not help in the long run. Instead, you should seek the root cause of your asymmetry which always stems from your foot up.
If you have some sort of cranial torsion (see images below) or any other general asymmetry, look to your shoulders. Is one higher? If so, focus on stretching your fascia (see images below) and relaxing overactive and stiff muscles with exercise. If not, does one appear shorter? If that's the case, then work on rotating your pelvis outwards or inwards as well as relaxing overactive neck and back muscles. If one leg appears shorter than the other, do all methods mentioned.
If your body is not the root cause and you have instead something like a c1 misalignment or skull deformities, seek professional help instead. No exercise or product will fix bad bones.
If you have some sort of cranial torsion (see images below) or any other general asymmetry, look to your shoulders. Is one higher? If so, focus on stretching your fascia (see images below) and relaxing overactive and stiff muscles with exercise. If not, does one appear shorter? If that's the case, then work on rotating your pelvis outwards or inwards as well as relaxing overactive neck and back muscles. If one leg appears shorter than the other, do all methods mentioned.
If your body is not the root cause and you have instead something like a c1 misalignment or skull deformities, seek professional help instead. No exercise or product will fix bad bones.

