How to design and arrange a 20 square meter barber shop?

See what you need, it's a bit trendy, with black as the theme and a little sparkle. It can be simpler inside. The door is a 3/ 1 glass door, and the inside is pushed out. Three-thirds is a big glass. Take the store as an example. There are barber chairs on the left and right sides, and the mirror (preferably a large floor mirror) is the cashier. There are more than 30 square meters of shampoo chairs behind the cashier.