Cut a piece of patterned paper measuring 9.5 x 9.5 inches square. Fold the square in half diagonally to form a triangle.
With the straight edge at the bottom, fold the left corner inward to meet the straight line at the bottom.
Repeat with the corner on the right hand side by folding it inward towards the left also meeting the straight line at the bottom.
Tuck the right hand corner into the left corner.
Fold the top triangles over – one to the front and one to the back.
Cut out some stars to decorate the envelope.
Use a piece of the blue star paper to matt eh front triangle onto and create a border. Adhere the stars and other embellishments for a finishing touch.