I think girls with square faces are more suitable for wavy hair, which makes their faces smaller. A wavy hair style will make the hair appear more swollen, and the contrast will make the face look smaller. The "bob" in wavy hair is a hairstyle that makes the face smaller. People who have their hair wavy generally have a smaller face. Whether they have a round face or a square face, a wavy head will generally make the face smaller.
Girls with square faces can also straighten their hair, but they must let their hair down, otherwise everything will be ruined. Straight hair is generally more suitable for people with smaller faces, but some people like to have long straight hair, so they can have straight hair, but they have to let their hair down and cover their faces. I see on Weibo that there are many girls with big faces who also have straight hair. When they put their hair down to cover their faces, their faces look very small.
If your face is really square, then I suggest you leave some bangs to cover your forehead, otherwise your face will look even squarer if your forehead is bare. Girls with square faces are more suitable for side bangs. You can also put some hair down on the side to cover the cheeks next to it. In fact, I think people with square faces can also try to have their hair parted in the middle, which can cover most of their face when it is let down.