How to Make a Box Out of a Card

From Sherri Osborn, former About.com Guide

Start off by making two folds along the side with the two lines you drew. First fold in the edge on the first line you drew, until it touches the second line. Then fold it in again on the second line.

On the other edges of the card, fold in each edge on the line you drew. Now fold in each of the pieces - tabs - you cut.

Now we can assemble the box...