How can I easily create playlist on clip+ combining songs from card and internal memory?

I am asking this question because I have a lot of music and would like to build a playlist that combines my favorite songs from both the internal and external memory banks.  I use WMP to sync my music to my Clip+ and have had no problems, so I was wondering if there was a way to accomplish this using WMP? And if not, perhaps there might be another way to do it, I’m really open to all suggestions here.