[Koha] data migration from excel to koha by marcedit

Hi I have koha 1.2.3 ,i'm working on mirgrate data from excel to koha by marcedit , which files need to mirgrate and process by marcedit ... ( items. biblioitem. bibliosubject ........ ) and how i mirgrate isuess and borrowers data into koha 3 ... shall i convert these files to excel or what ??? thank you at all