Take a colored piece of paper and place it face down on the table.
Fold the paper in half diagonally.
Lay the paper down in front of you so that the longest edge is facing you.
Take the bottom right corner and fold it over the main area of the piece of paper so that the corner touches the opposite edge, and so that the top of the newly folded edge is parallel with the bottom of the piece of paper.
Do the same thing to the left corner, folding it across the main area of the piece of paper until it touches the opposite edge. The top edge of this fold should be exactly on top of the top edge of the previous fold.
Take the outer layer of the very top corner and fold it down until the corner touches the spot where the bottom of the other two folds meet. You should see a pattern in the shape of an "X".
Do the same thing to the other layer, but in the opposite direction.
Spread apart the two layers on the top and gently push the sides in.