The waiter’s personal hygiene, such as clean and short nails and the fact that the hair is up, is interpreted by the guest as a good sign. Loose nails on a waiter/waitress are a major source of bacteria and should be strictly forbidden when working with food. They collect a lot of bacteria from toilet visits, dead skin and so on.
If you have long hair, it should be set in a tail or in a knot depending on how long hair you have, this is also done to open up and get the hair away from the face as it is more inviting for the guest when they talk to the waiter / waitress.
How you make up is also interpreted by the guest, it is your personality that should be emphasized. If you are heavily made up, avoid sharp lines and make sure that the makeup goes together with each other and your skin.
If you have a makeup with different patterns and colors, it depends entirely on which workplace you work in, which genre and niche.