How to make a closed flat square origami box

(page 2)

1st picture of closed flat square origami paper box

01.

Let's start with the back side of the paper facing up.

Prepare to apply a horizontal "Z-fold" and then unfold.

2nd picture of closed flat square origami paper box

02.

Apply the horizontal "Z-fold" of the step #1 and then unfold.

Prepare to apply a vertical "Z-fold" and then unfold.