1)  Fold the sheet in half, then unfold. It's suggested to face the convex side of the crease up as shown, as this will preserve its direction in the finished airplane, but facing it down is ok.
			2)  The angle of the main diagonal folds (two symmetrical folds, the first of which is shown above) is essential to the perfect Sharky. It has to be very close to 30 degrees, with very little latitude for error. The good news is that if your angle isn't perfect you can still usually turn your plane into an excellent Sharky variation. The correct angle can be generated using the linear dimensions shown on the next page. The translation of the diagonal folds along the length of the page may be varied slightly.
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