If you have the old version you should download the new and improved version now! Find it in both PostScript and PDF (and several other dials) at my sundial page.
Fold the paper lengthwise along the printed centerline. If you are careful you can get the crease right on the line. I hold it up to a light and make sure the dial faces on the two sides are lined up before I crease it. You may find it helpful to score the fold lines. An empty ball point pen and a straight edge work great. If you are using a dot matrix printer the compression from the pins helps the paper fold nicely.
Next fold the paper on the other line. If you are in the northern hemisphere you'll fold it so the latitude scale is on the outside.
Take an ordinary sharpened pencil and poke it through the paper in the center of the dial. This is the most difficult part of assembly. If you take your time and work at it you can get the pencil right through the center. You can cut away the excess paper to make the hole neater if you wish.
Poke a thumbtack through the latitude scale at your latitude. Slide the paper along the pencil until they form a right angle and then stick the eraser onto the thumbtack. For greatest accuracy use a pencil with a new eraser and carefully put the tack into the eraser right at the edge. If you wish you can put tape or glue at the hole where the pencil passes through. This is especially helpful if the hole gets enlarged through wear.
You are now ready to tell time. Place the sundial somewhere in the sunshine so that it is facing north. That is, the pencil should be pointing north (really the pencil should point almost directly at Polaris, the "North Star.") Be sure the paper is perpendicular to the pencil. Read the time.
Find other sundial's at my sundial page.