Getting Ready for ILS Migration involves four key steps: 1) Identifying match points like ISBNs and ISSNs to transfer bibliographic records, 2) Cleaning the catalog by weeding out brief records and ensuring consistent call numbers and formats, 3) Cleaning the patron database by updating expired patrons, fines, and categories, and removing unnecessary data, and 4) Mapping how data will transfer from the old to new system, including exceptions, and using tools to test and review the migration.