What type of business structure will you have – a sole proprietorship, partnership, corporation, limited liability company, or limited partnership? You may want to consult an attorney or accountant for more information on which structure is best for you. You may also want to register a DBA (Doing Business As) at the Hillsdale County Clerk's Office (even if you have chosen something other than a sole proprietorship) to ensure your business name is not taken by another Hillsdale County business. FYI: The County and State do not cross-reference their lists, so only in Hillsdale County is your DBA protected.
Once you determine your structure, register your business with the State of Michigan.