The Clerk of Court in the county where the individual resides will have sample forms and documents that can be used to get someone help. The papers are required to be notarized and sworn under penalty of perjury. A Judge assigned to hear those cases in the county will review the Petitions and sign whatever orders they deem appropriate. There may be hearings scheduled at which both the concerned person and the impaired or ill person are required to appear. Counsel is normally available for the impaired or ill persons, if requested.
It is a good thing to try to get help for someone who needs it – mental illness and substance abuse are both problems that can make it very hard for a person to realize on their own that they need help until it is too late.