How can you get a divorce from an incarcerated spouse for a 1 in Missouri?

Your question is confusing. "How do you divorce a prisoner for 1." What does "For 1," mean? Otherwise, anyone divorces a prisoner just like anyone divorces anyone else. You go to the court that handles divorces and file for divorce. You serve papers on the other party. The prison has a process whereby they will bring the prisoner to a special holding cell where the person serving the papers can serve them.

The prisoner may represent himself or herself in court in person or by telephone or through an attorney. It varies according to location.