If you will be covering the outside or inside of your box with fabric, you can omit this step. Fabric hinges help prevent the paper covering the box from tearing at the folds, and allow the box to be opened and closed more frequently.
Make Fabric Hinges Cut four lengths of fine woven fabric at least one inch wide and the length of your box base. If you prefer you can cut the lengths from bias tape which has been ironed open. That is what you see in the photos in these instructions. If you will be covering the box sides with fabric, proceed to the step on covering the box.
Hinge the Inner Sides of the Box - Take your smallest remaining side piece and lay it beside the base of your box so that it is against the base of the box, even with the edge furthest away from the fixed sides, and overlapping one of the fixed side edges. Use the glue applicator to apply a good coating of glue to one side of your fabric hinge and carefully glue it across the base of the box and the base of the side, keeping roughly equal amounts of fabric on each side as shown in the photo above. Press down on the fabric gently to make sure it is thoroughly glued to the box pieces, especially on the edges. Check that the hinge is in the correct position by moving the side into the upright position and checking that there is enough play in the hinge to allow this, but keep the side of the box tight against the base. Lay the side down again until the hinge has dried. (After adjusting it if necessary).
Line up your final box side flat against the box base so that the edges of this side will cover both other edges of the box sides when this side is in the upright position. Glue and apply the fabric hinge the same way you did for the first side. Leave the hinges to dry in place.