Gather a sheet of paper
Place the paper flat on a surface
Fold the paper in half lengthwise
Unfold the paper
Fold the paper in half widthwise
Unfold the paper
Fold each corner toward the center
Fold the top and bottom edges toward the center
Fold the left and right edges toward the center
Fold the paper along the existing creases to form the box shape
Tuck the flaps into place
Press the edges firmly to secure the box