Easy

Also need:
59 x 37 cm / 23 1/4 x 14 1/2” piece of fabric for lining
Matching sewing thread

From the mag:

This charming pajama case adds a touch of retro glamour to any slumber party. Worked in one easy piece in stockinette with garter-stitch edges, it has a fold-over flap and is lined with a pretty print fabric.