Step 1:
Glue two squares together or fold a large square in half.
Fold over the lower line and prefold over the upper line.

Step 8:
Fold over this line.

Step 6:
Glue the edges on the lower part together

Step 11:
Pull the pleats outwards

Step 10:
Make the same two folds on the back (mirror wise). Then glue the edges together.

Step 9:
Slide the left end into the right end, see arrow. Then glue the edges together.

Step 5:
Fold the prefolded lines to the left.

Step 7:
Fold over this prefolded line.

Step 3:
Fold to the centerline. Then unfold the folds of step 2 and 3

Step 2:
Prefold in half, then fold both edges to the prefolded centerline.

Step 4:
Prefold these two lines into the right direction.

Done!
This is a video tutorial for making the peplum skirt:

Picture: Dollhouse office made out of paper and Origami models

And this is a 'real' peplum skirt, great office outfit!