Science has not caught up with facial musculature. I know of only one double-blind study monitoring the results of facial exercises over 120 days.
Consistent facial exercise is significant, as it increases higher cheekbone volume, decreases lower-cheek buccal fat volume, tones the philtrum region, increases the width of the masseter muscles giving you a squarer and thicker jaw, tones the jawline structure, neck, and submental-fat region, augments the width and thickness of the chin, and overall, brings greater symmetry to the face.
Although some do facial exercises by virtue of squeezing their face during high-intensity compound movements, some do not.
One product that I found superior for facial exercise than exercising alone is the
Jawzrsizer. Commit to 10 sets of 100 reps per day, and in 90 days you will see a marked improvement.
Also keep a clean diet with low-glycemic or low-inflammatory carbs (see Paleo diet) primarily and drink one-gallon of water day to minimize bloating and accentuate your facial aesthetics.