You will need to start with an idea for a business. This idea then needs to be presented for approval to an approved ‘endorsing body. The Home Office provides a list of endorsing bodies covering various sectors and fields that are permitted to endorse a business idea for the purposes of this visa application.
You will need to evidence through a business plan and supporting documents that your business idea is viable, innovative and scalable.
If you secure endorsement, you have three months to make your visa application to the Home Office.