See here also: http://tinyurl.com/8bx5r|
The new system was causing some confusion when we arrived. Particularly because half of us had the old green cards and half had the new vouchers.
If you have the old green cards you still have to go to the counter where you purchase the cards. They will take the green card and print up the exit portion of the voucher as seen in the pics linked above.
Once everyone has the new style vouchers, they must complete the new blue forms and proceed to clear immigration with both documents in hand.
Hang on to your exit vouchers. You must present them along with the blue form again when clearing immigration on departure. Might as well take an extra copy of the blue form when you arrive and complete it in advance. On the bus to the airport only adults were given the forms. At the airport we were told that everyone had to complete them and they were handing them out for children as well.