How to COPY a existing SAP Script to a new Script for modifications?

Hi Experts,

I need to copy a SAP Script of Z_MEDRUCK_PO to Z_MEDRUCK_PO_MODIFIED_HEADER_TEXT_LOCATION, in order to change the location of header text printing from bottom to top.

so, request u that, let me know, How to COPY a SAP script? step by step, if time permits.

thanq