What are the procedures to become an company secretary in UK?
You need to tell Companies House. If it’s a new company, just put the name, address and other particulars of the company secretary on Form 10 [link 1]. If it’s an existing company, assuming the board of directors agree, I think it’s Form 288a [link 2]. Be sure that you meet the requirements, if applicable. If, for example, it’s a public company, see [link 3]. This is just my best effort at an answer, you might want to seek a qualified professional’s assistance, or if you contact Companies House direct, they might be able to point you in the right direction.