Start with a square sheet of paper
Fold the paper in half horizontally, then unfold
Fold the paper in half vertically, then unfold
Fold each corner into the center
Fold the top and bottom edges into the center
Unfold the top and bottom edges
Fold the left and right edges into the center
Unfold the left and right edges
Lift two opposite sides to form the box walls
Tuck the side flaps inward to lock the shape
Press the corners firmly to secure the box