There are certain tours on which UK citizens may not need a visa to enter China - you can find exact information here. If these conditions don't apply to you, you may need a visa. You can start the application process online; if you click here you will see links to information about the Chinese visa system, instructions for getting one and so on.

You may need a tourist, student, business or work visa; if you are not sure which kind of visa is right for you, you can get in touch with the London application centre directly (the address, phone number and office hours are near the bottom of the home page.) Also, on the right of that page there is a link to get help by email, which may be easier.

You can also create an appointment to discuss your application; again, on the home page there is an 'appointment' tab.