Not any different than for a passenger airline....write to the LBA, get the application papers, employ the people, get hands on the aeroplane, set up the maintenance, pay the application fee, fill in the bits and send the papers back, await the inspectors to come, explain, sort problems, alter set up, amend the manuals, pay more money, wait 6 months, fail the feasibility study, re-adjust papers, convince the bankers (fifth time) and once you have the docs, you can proudly lift off....
Have done this procedure a couple of times in several countries...do not expect real information or help without offering a reasonable amount of money for it.
Mail me if you want further contact.