You will need a pair of scissors and an A4 80g/sqm office paper. (No sweat, the design can modified for inferiour formats.) No glue or tape is needed. ...nor batteries.
Step 1: Print or view the drawing, cut the paper to pieces.
The drawing is a high precision machine drawing prepaired with programs used by NASA. If it is followed carefully, all parts will fit nicely together. For these reasons, it is recommended that the first one or two boats you make are built from printouts of this file.
Don't cry if you don't have a printer. The design is perfectly possible to follow just by viewing the drawing on your screen.
We start here by cutting the pieces apart along the solid lines. If you want fins, cut them out too. If not, you can leave them where they are. They can be used as a foredeck if left attached to the sail.
Step 2: Prefabricate the easy parts
The beam is folded up-down-up-down...
The slits that will accept the hulls are most easily cut when the beam is completely collapsed.
Note that the drawing shows two fins -- fixed rudders -- that can be cut out from that quarter of the paper. The pictures, however, show the original design without fins.
Since the fins will be folded into the hulls, now is the time to decide if you want them or not. For simplicity, leave out the fins the first time. (To be perfectly honest, I have not tried them out on the water, so I cannot tell if they will make any perceptible difference. The original design does not keep a straight course downwind, so it may pay off to experiment with them.)