Tape down the other side so it’s wrapped all the way around.
Lay the first edge flat down the bottom or top edge, then holding the flat, pinch the side seam, repeat for the next side.
Hold both of those side darts flat, and fold the bottom flap over (If you want it to be square) or leave it triangular and fold it up as is and tape it down. If you folded it over to make it square, fold it up again and tape it down.
Repeat step for for the remaining side.
Place your ribbon or string flat across one side (make sure to leave it long enough to wrap twice around and make a bow.
Flip the box over, criss-cross the ribbon/string in the back, as shown, then wrap it around the other side of the box until you arrive back at the front.
Tie a knot then a bow.
Optionally, if you’re using balloon type ribbon, pull it with a scissors’ edge as shown to make it curl.