1) Navigate to your podcast page on the Y! Podcasts site (e.g. http://podcasts.yahoo.com/series?s=bb9bd351bc27e4ec039d10dfe3a74a2f )

2) Highlight and copy the string of characters following the "/series?s=" (in the above example, the string would be: "bb9bd351bc27e4ec039d10dfe3a74a2f")

3) Paste this string into the box next to "Your Series ID on Yahoo! Podcasts:"