This is a very simple procedure. Log on to the Web Server for the Workplace (not directly via SAPGUI on the Workplace Server System) and click the spanner icon:

A window appears where you can enter the new BSP application URL and a name. You can copy the URL page using Cut&Paste either from the browser line or from the development system of the BSP page (tab page Attributes on the Business Server Page in the Object Browser).

Choose Transfer. The new URL has been entered.