How do I create a flexfield that can be used to group chart of accounts members for reporting?

I assume that I need to create a General Ledger Descriptive Flexfield using a Module of General Ledger but I need more guidance. We would like to use this Flexfield for reporting and analysis. Can it be used in Smart View? I assume that we can enable it for use in FDI. As an example, we want to create a flexfield that can be used to group cost centers with the same flexfield value for reporting purposes.