No differently than opening a PC-Created Word document on a PC or a
Mac-created Word document on a Mac... or a PC-created Word document on a
Mac.
If you're encountering some sort of a problem you'll need to give a clear
indication of what that problem is. Specify your update levels of Office on
both Windows & Mac, what method you're using to open the files, how they're
being transported, the exact wording of any error messages, as well as a
description of what the document content is.