How do I copy my set program to multiple days of the week with the Haverland RC Wave?

First, make sure you've saved your newly set program before you copy it to other days of the week. You can find the ‘save’ icon next to the ‘copy’ icon in the side menu. If the menu times out, it will autosave your program. So, you can either save it manually, or let it time out and autosave, before you start copying to other days of the week.