You will need:
6 squares out of medium / heavy weight chipboard (I used 4" squares in the pictures)
7 - 8 strips of cardstock 1" x size of square" (1" x 4") - folded in half lengthwise (if you make 3" cubes your strips will be 1" x 3") (7 strips if you want a lid that opens 8 strips if you want a box that is closed)
Adhesive (I used ScorPal tape - Sookwang tape)
Connect the squares with the strips of cardstock. I put my strips for the cube on the interior (but exterior is fine also) Only connect 1 side of lid if you want a box that opens.
Now decorate, embellish, paint, give it feet, and fill it however you wish - here's an ATB I made using this technique a little while ago: Steampunk Victorian ATB Night Light
Here's some photos to help you on your cube making journey.