Any visa required national must make an application. In order to do this you must collate and provide a list of supporting documentation. In most cases this will include your passport, passport photographs and visa application form.

To support the application type, typically the following additional documents may be requested: business support letters, invite letters / official govt invite letters, contracts of employment, resumes, proof of qualifications, birth / marriage certificates, travel itineraries, proof of accommodation, bank statements, criminal record certificates, medical documents / proof of travel insurance, UK residence visa (if applicable) and more.

Each document type will also have its own list of requirements such passport validity or certain mandatory content in the support letters etc. Failure to meet all requirements is subject to outright refusal and could also impact future visa applications.