When writing a Prism script for the Mac, how do I separate disk names, folder names, and file names?

For windows, you separate with backslashses.  Prism 5 mac accepts slashes or colons. For example:

SetPath "HD:John:Prism Scripts"

or 

SetPath "HD/John/Prism Scripts"

If you choose Get Info from a folder, you can see the path. Enter exactly the same way into the setpath command. Don't forget the leading slash if you omit the volume name  (the trailing slash is optional, omitted below). 

SetPath "/Users/hmotulsky/Dropbox/Intuitive Biostats 2nd edition/Figures"

A trick to copy and paste the path. Drag a file from the folder into Text Edit. Just the path will appear. Copy and paste into the Prism script.