Come up with a name, get a lawyer, and have them register your company. Then comes all the paperwork involved, like PAYE Schemes, tax books, and all that other junk. Or you could do what most people do and just develop projects under the name only. But actually register. And always, always, ALWAYS become a limited company! Then you are safe in case anything happens, because on paper you are not your company. But you can still own the company.