Here are some signs which you can download to advertise in Chinese that you have a Chinese menu. They are designed to be printed off on a sheet of A4 and displayed in the window, but once you have downloaded them, do with them as you wish.
They have text in Chinese and English, but the English is just for your reference and so is in a much smaller font.
Welcome! We have a Chinese Menu.
Traditional British Food with a Chinese Menu.
Chinese Menu.
Chinese tourists most welcome! We have a Chinese menu!
Welcome! Try some British food. We have a Chinese menu.
Please ask for our Chinese menu.