Step 8: Add backing and put together
Take your second rectangular piece of the can (the uncut piece), turn it over and center the cardboard piece on it. Fold all sides over the cardboard (this piece has indentations traced all around it, making it easier to fold it down over the cardboard).
Now place each rectangular piece back to back (cardboard side to cardboard side). Using electrical tape or duct tape, tape over the edges to attach both pieces to one another. I started out using yellow electrical tape, but decided I liked the red tape better.