From the pattern site:

Materials:
WW yarn in a soft pink or light rose
Fiberfill
Scraps of black, white, blue and red felt
Sewing threads to match the felt colors
Sewing needle
Yarn needle
Size F hook

NOTES:
I tend to prefer to join my rounds when I work, but if you prefer to use continuous rounds and stitch markers, that’s also good. Whatever is most comfortable for you.

Gauge isn’t really important, as long as the hook, yarn and your tension result in a fairly tight stitch so that the stuffing doesn’t show thru.