The nandroid backup you should have made is in the clockworkmod folder. This you need to transfer to the other uSD card for sure. Anything else is up to you.
It's a good idea to put all the info you need on the PC as well, just in case something happens to wipe all data from your uSD card.
I did this by mistake once myself. Because I made a backup folder on my PC it wasn't a problem, just transferred the info back to the uSD card.