Take a regular sheet of notebook paper and write your note on it. Then, fold over the top right corner so the top edge of the paper is lined up with the left edge. Fold the top right corner over again to make a triangle shape at the top of the paper. Flip the paper over, then fold the bottom up about 1/3 of the way. Fold the bottom up a second time, then fold down the point of the triangle you made and tuck it under the diagonal fold on the back of the note.