Every little boy knows how to make a ninja mask out of a T-shirt, but if you want your mask to be authentic, you need to learn how to make it out of a plain strip of fabric, wrapping it around your head just like the real ninjas used to do. Add the correct pants and a ninja weapon of choice, and you will be ready to take on anyone who dares to challenge a real ninja.
Lay out the fabric, then fold it diagonally, from one corner to the opposite corner. This will leave you with a right triangle.
Fold the large right triangle into a smaller one by matching up the 45-degree corners. Pick it up by holding each corner in one hand, with the point of the triangle up.
Lift the triangle above your head and bring it down over your head, so that your head is inside the folded part of the triangle. If you look up, you should be able to see out between the sides of the folded part.
Lower the ends of the triangle snug against your face, leaving only your eyes showing. Tie the ends in a firm knot behind the back of your head.
Wrap the smaller, second piece of fabric around the lower part of your face. Wrap it by centering the middle of the fabric in the back of your neck, then bringing the ends around to the front, then around again to the back. Tie a knot. This part is optional as not all ninjas wore this second piece of fabric.