Spread a small amount of glue on the rabbets you cut in the end of your box. Spread a small amount of glue on one end of the base, and one side of the base. Press fit the base of your box into the rabbet on the end of the box.
Run a small amount of glue on the end of the side that fits the box end, and press the side onto the rabbet on the end of the box, and up against the glued edge of the box base. The box base and the side will be glued in a simple butt joint, where one piece glues flat on it's end to the side of the other piece.
Finish gluing the box by adding the final side onto the end and base. Then add glue to the other rabbets on the final end of the box and glue it to the sides and base.
Carefully wipe away any excess glue that come out of the joint seams.
See the next step for clamping the box.
