Contact the UK Border Agency to locate a visa application center (VAC) near you. You have the options of applying for a visa by mail, courier, online or in person. A VAC staff representative can help explain the advantage of each method and which may be the most convenient for you.
Provide your child's valid passport and recent passport photo, which should be a color photograph of the entire face, 45 mm x 35 mm in size and taken against a light-colored background. It must be printed on normal photographic paper of clear quality.
Make an appointment at the VAC to hand in your child's paperwork, and to provide biometric data--10-digit finger scans and a digital photograph. Both will be done at the same time and shouldn't take longer than 15 minutes.
Pay the visa fees, which are nonrefundable and normally paid in the currency of your country. The Entry Clearance Officer at the VAC will typically process your child's visa in two to 15 days. You can pick up the completed visa from the application center or designated consulate.