**Use your flowchart, periodic table, and polyatomic ion sheet to do this.
If your formula starts with a metal (and only has one oxidation number), there is nothing special to do.
If your formula starts with a metal with more one oxidation number (transition metal), you will need a roman numeral. You may have to use oxidation numbers backwards to figure that out.
If your formula starts with an nonmetal, you will need prefixes.