I would like help filing a contempt of court order in Platte County, MO against my ex husband who owes me money from the settlement in divorce decree.

You need to file for a Motion of Contempt according to the local rules in the Circuit or the General Rules of that Circuit.  If it is a significant amount it is worth retaining good legal counsel who will make the process vastly more efficient.  The results will also likely be more favorable with counsel than without.