Make an outside reverse fold on the right section by pushing the outer edge of inward, and pulling it upwards until it reaches the diagonal fold you made. Make an inside revers fold on the left section by pushing its inner fold inwards and pulling it upwards until it reaches the diagonal fold. Press the folds again to neaten them.
Turn the paper over, and repeat this step on the other side with the lower/left flap.
Flip your paper over, and repeat this step on the other side.
After narrowing the diamond, take the right flap of each side and fold it over the left flap.
