Summarize the following:
Start with a sheet of paper that's 8.5 inches (21.6 cm) by 11 inches (27.9 cm). Place one of the halves on a flat surface in front of you. Discard the other half or save it to make a second origami boomerang. Use your finger to make a crease along the fold. Unfold the piece of paper. Bring the edges of the paper to the center crease when you fold the sides in half. Make a crease along both folds with your finger. Leave the sides folded in. Bring the top edge of the paper down to the bottom edge. Make a crease along the fold with your finger. Leave the paper folded in half. Crease the folds with your fingers. Go over these creases several times so they're really defined. Unfold the corners. When you're finished, you should have a thin horizontal rectangle with 2 triangles pointing at each other in the middle. This is the flap of paper that's closest to you. After you unfold it you should see a diamond in the creases on the lower half of the paper.

Summary:
Use scissors to cut a sheet of blank paper in half lengthwise. Fold the piece of paper in half lengthwise. Fold the paper in half lengthwise on both sides of the crease. Fold the paper in half crosswise. Fold the top left and right corners to the center crease. Unfold the crosswise fold you made and turn the paper so it's horizontal. Unfold the flap of paper on the bottom half.