Get a one dollar bill, fold four times, one for each corner.
After folding the four corners. Notice how the bill has the marks of those folds.
Fold both ends of the bill by pulling in the sides, in order to have the shape of a triangle
Bill with both ends folded into triangles
Fold both ends (tips) of the triangles into the center of the bill.
Fold the four sides of the triangles (two per triangle) towards the inside. Already amazing, uh?
Fold both sides towards the back of the bill - here you see the right side folded (looks like it disappeared).
Bill with both sides folded backwards
The bill now has three differentiated thirds. Fold them as shown. Right third to the left. Left third to the right.
This is where magic starts. Insert both corners into the sleeves created by the folding. Here you see how to insert one corner.
Inserting the second corner. Almost there!
The two corners are now inserted in the corners. We are done! Note how tight it looks.
The other side of the bill after finishing. Hand it over to a friend and ask them to unfold it without tearing it apart. I had my first folded bill in my wallet for 10 years. It brought me luck :-)