This is a very handy paper ninja star for part time ninjas. (Full time ninjas, sorry you might wanna make a real one)

Step 1: What You Need

All you need is two square pieces of paper. You can use paper thats already a square or take a normal 8 1/2 by 11 piece and make it a square. I used origami paper so its already a square ^_

Step 2: Lets Get Folding

First fold the paper in half, then fold it in half again.

Step 3: Some More Folding

Fold the rectangle in half the other way now. Then unfold it and move on to the next step.

Step 4: And Again Some More Folding

Now, this might seem a little hard, but it is easy. Lets say that each rectangle has 2 parts that are separated by the fold you made. On one of the rectangles fold one side up, on the other rectangle fold that side down, they have to be opposite.

Step 5: Almost There

Now fold the other half of the rectangle the other way, the do the same on the other rectangle.
The two pieces you have should be mirror images just like whats shown in the picture.

Step 6: Just a Little Bit More Folding

Now, you need to fold the all little squares so that they make triangles. What you end up with will look like whats shown in the picture.

Step 7: Finish Folding

Now fold the triangles on both pieces so that you make a trapezoid looking figure, you can see what i mean in the picture. This fold will help you when you put your two pieces together. Thats it, your done folding!

Step 8: Together at Last

Unfold the triangles so that you back to the weird shape. (the first picture) Now, one side of the rectangle has no "crack" and the other side has a "crack," or a "slit". Take the two rectangles and put them together so the two un-cracked sides are touching, and the cracked sides are facing out. I hope you understand what i mean.

Step 9: Tuck It In

Now, tuck the corners of the triangles into the little crack. Then flip it over and do the same. Your done, congratulations, and thanks for looking at my instructable, please comment and tell me what you think.