Hat boxes are useful not only for safely storing men and women's hats, but they can also be utilized for gift boxes, decorative pieces that are color-coordinated for a particular room, or for lightweight individualized keepsake containers. Since the hat box is used to hold more than a hat, you can make your own and personalize the box to fit your desired shape, design, or color scheme.
Take your chosen color of poster board and lay 2 pieces together, flat on a sturdy table or on the floor. Put something like cardboard under the poster board to protect the table underneath from cut marks. Decide what size you want for the base of the hat box and use a pencil to outline this shape onto the poster board (either round or square). Cut out this outline with a craft knife through both layers of poster board. The edges may be a little rough, so use a small piece of extra-fine sandpaper to smooth out the roughness. You now have the base and lid for your hat box.
Take another piece of poster board, hold it on one of its sides above the base with the chosen color facing outwards, then turn it to make a cylinder (for a round hat box), or fold it at each corner to make four sides for a square hat box. Don't be concerned about securing it to the base yet: you are just setting it atop the base to square or round it off for the sides. After you have shaped it, secure the bottom of the cylinder or square with a clothespin so it will retain its shape. Then cut off the extra overlapping width. This is also the point where you decide how high the sides should be, and cut off the undesired height. Sand off the roughness as needed.
Remove the clothespin, and place glue up and down the edges of the cylinder or square. Press these ends together and secure with clothespins. Allow to dry. You now have the sides (cylinder or square) of the hat box to fit atop the base. Apply a thin strip of glue along the edges of the base. Set the cylinder or square form atop the base, aligning it onto the glued area. Press even strips of paper tape inside and outside the hat box at the base--all around the hat box. Fold the tape neatly at each corner (if the hat box is square).
Take the lid that you cut in step 1 and lay it flat. Select another section of poster board and repeat steps 2 and 3 to make the band for the lid--but only cut a 2-inch or 3-inch high strip from the poster board. Form the strip around the lid and glue onto the lid. Allow to partially dry then fold strips of paper tape around the inside of the cylinder or square lid, pressing it down neatly. You now have the completed lid for the hat box.
Decorate the dried and assembled hat box with your choice drawings, craft decor, or collage pictures. The inside of the hat box can be lined with fabric such as velvet. Simply measure the fabric the same way you measured the poster board for the base and sides and glue the fabric to the inside.