>>4584
It makes your jaw grow forward instead of downward. You don't have long face then, which is usually ugly if you check the beauty standard ratios. The problem is, you had to do it when you were 7-9 when you face had been growing. There are also many other benefits of keeping your tongue on palate all the time and breathing only through nose so you should definitely do that, but it won't impact your face much anymore as it doesn't grow that much at this point.
You can, however, change your face tremendously with face yoga exercises. They work always on anyone at any age. One that works after just a week and gives you more manly jaw is protruding your lower jaw and then looking on ceiling while the neck remains straight. You should feel some strain on the sides of your jaw.
Don't overdo it. Also, if you feel strain only on one side, it means you chew more with this side and it's more developed. Perhaps you had pain in teeth for half a year and you get used to chewing on one side or smth. If it's true, then control yourself by taking photos at the beginning and during the week because you don't want to have rough jaw on one side, and girly on another. And these exercises actually change your face enough to confuse people as they notice you changed.
Combine with lymphatic massage, freezing water on face, green tea and facial masks for improved results (just no freezing water right before mask because you close pores)