Learn to make this easy origami heart made from a triangular sheet of paper. It takes less than 5 minutes and if you start with a square sheet of paper, you can cut it into two triangles and make two hearts!
Heart from Triangle instructions
Start with a square sheet of paper with the white-side facing up. Fold and unfold along the diagonal in both directions.
Cut the paper along a diagonal to make an isosceles triangle.
Fold down the peak of the triangle: make the fold at
approximately 1/3 of the way down (doesn't have to be exact).
Fold up the left and right bottom-corners so the edges
meet in the middle.
Turn the model over.
Fold down the corners of the paper as shown; this makes a heart shape.
Round the heart-shape by folding in the pointy corners.