[Koha] Migration of Multiple copies

Dear Mr. Robin, Can you share with us the step by step process of data migration of multiple copies of single titles in MARC21. The standard practice what I have done is to keep the biblio number same and then changing the local field details in 952 and making sure that barcode and copy number changed. But not able to do the same and facing some problem. Appreciate your suggestion and help. Thanks and Regards R Sunil Kumar Library Technologist