Đo chiều dài và chiều rộng khuôn mặt. Xem xét viền hàm dưới. Quan sát vùng trán và đường chân tóc. Sử dụng các quan sát trước đây để xác định hình dáng gương mặt. Chọn kiểu mái hợp với gương mặt. Đừng quên tình trạng tóc của bạn!

I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
This will help you rule out some face shapes and help you get a general sense of your look. Use a mirror and measuring tape if you need help.  If your face is about equally as long as it is wide, you most likely fall into the round, square, or heart shaped category.   If your face is a bit longer than it is wide, you may fall into the oval, square, or heart shaped faces. Your face is not round.  Oval-shaped faces are considered an ideal face shape for all hair styles. Your jawline falls at the b